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Hybrid ldpc and stbc algorithms to improve ber reduction in ofdmIAEME Publication
This document discusses improving bit error rate (BER) performance in orthogonal frequency division multiplexing (OFDM) systems using hybrid low-density parity check (LDPC) codes and space-time block coding (STBC). It first describes MMSE and LS channel estimation techniques in OFDM and an adaptive modulation and coding WiMAX system. It then proposes using LDPC codes with STBC across multiple transmit antennas to achieve coding gain and diversity gain. Simulation results show the hybrid LDPC-STBC method provides better BER performance than STBC alone, especially at low signal-to-noise ratios in flat Rayleigh fading channels.
A New Bit Split and Interleaved Channel Coding for MIMO DecoderIJARBEST JOURNAL
Authors:-C. Amar Singh Feroz1, S. Karthikeyan2, K. Mala3
Abstract– In wireless communications, the use of multiple antennas at both the
transmitter and receiver is a key technology to enable high data transmission without
additional bandwidth or transmit power. MIMO schemes are widely used in many
wireless standards, allowing higher throughput using spatial multiplexing techniques.
Bit split mapping based on JDD is designed. Here ETI coding is used for encoding and
Viterbi is used for decoding. Experimental results for 16-QAM and 64 QAM with the
code rate of ½ and 1/3 codes are shown to verify the proposed approach and to elucidate
the design tradeoffs in terms the BER performance. This bit split mapping based JDD
algorithm can greatly improve BER performance with different system settings.
This document analyzes and models the Enhanced Data rates for GSM Evolution (EDGE) mobile communication system. It develops a MATLAB simulation of the EDGE system to model channel coding, modulation, interleaving, burst building, multipath fading channels, channel estimation and detection. The simulation tests the system over additive white Gaussian noise and Rayleigh fading channels. Results show received signal quality decreases with lower signal-to-noise ratio, and fading channels require higher SNR to achieve the same performance as non-fading channels.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
PERFORMANCE OF WIMAX PHYSICAL LAYER WITH VARIATIONS IN CHANNEL CODING AND DIG...ijistjournal
The document analyzes the bit error rate (BER) performance of the WiMAX physical layer using different concatenated channel coding schemes and digital modulations under realistic channel conditions. Computer simulations show that a WiMAX system using concatenated CRC-CC channel coding and QAM modulation performs better than one using RS-CC coding, achieving a lower BER at a given SNR in additive white Gaussian noise, Rayleigh fading, and Rician fading channels. Specifically, the CRC-CC coded system reaches a BER of 10-4 at around 6 dB in AWGN channels, compared to over 6.6 dB for RS-CC coding.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Lightweight hamming product code based multiple bit error correction coding s...journalBEEI
In this paper, we present multiple bit error correction coding scheme based on extended Hamming product code combined with type II HARQ using shared resources for on chip interconnect. The shared resources reduce the hardware complexity of the encoder and decoder compared to the existing three stages iterative decoding method for on chip interconnects. The proposed method of decoding achieves 20% and 28% reduction in area and power consumption respectively, with only small increase in decoder delay compared to the existing three stage iterative decoding scheme for multiple bit error correction. The proposed code also achieves excellent improvement in residual flit error rate and up to 58% of total power consumption compared to the other error control schemes. The low complexity and excellent residual flit error rate make the proposed code suitable for on chip interconnection links.
Hybrid ldpc and stbc algorithms to improve ber reduction in ofdmIAEME Publication
This document discusses improving bit error rate (BER) performance in orthogonal frequency division multiplexing (OFDM) systems using hybrid low-density parity check (LDPC) codes and space-time block coding (STBC). It first describes MMSE and LS channel estimation techniques in OFDM and an adaptive modulation and coding WiMAX system. It then proposes using LDPC codes with STBC across multiple transmit antennas to achieve coding gain and diversity gain. Simulation results show the hybrid LDPC-STBC method provides better BER performance than STBC alone, especially at low signal-to-noise ratios in flat Rayleigh fading channels.
A New Bit Split and Interleaved Channel Coding for MIMO DecoderIJARBEST JOURNAL
Authors:-C. Amar Singh Feroz1, S. Karthikeyan2, K. Mala3
Abstract– In wireless communications, the use of multiple antennas at both the
transmitter and receiver is a key technology to enable high data transmission without
additional bandwidth or transmit power. MIMO schemes are widely used in many
wireless standards, allowing higher throughput using spatial multiplexing techniques.
Bit split mapping based on JDD is designed. Here ETI coding is used for encoding and
Viterbi is used for decoding. Experimental results for 16-QAM and 64 QAM with the
code rate of ½ and 1/3 codes are shown to verify the proposed approach and to elucidate
the design tradeoffs in terms the BER performance. This bit split mapping based JDD
algorithm can greatly improve BER performance with different system settings.
This document analyzes and models the Enhanced Data rates for GSM Evolution (EDGE) mobile communication system. It develops a MATLAB simulation of the EDGE system to model channel coding, modulation, interleaving, burst building, multipath fading channels, channel estimation and detection. The simulation tests the system over additive white Gaussian noise and Rayleigh fading channels. Results show received signal quality decreases with lower signal-to-noise ratio, and fading channels require higher SNR to achieve the same performance as non-fading channels.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
PERFORMANCE OF WIMAX PHYSICAL LAYER WITH VARIATIONS IN CHANNEL CODING AND DIG...ijistjournal
The document analyzes the bit error rate (BER) performance of the WiMAX physical layer using different concatenated channel coding schemes and digital modulations under realistic channel conditions. Computer simulations show that a WiMAX system using concatenated CRC-CC channel coding and QAM modulation performs better than one using RS-CC coding, achieving a lower BER at a given SNR in additive white Gaussian noise, Rayleigh fading, and Rician fading channels. Specifically, the CRC-CC coded system reaches a BER of 10-4 at around 6 dB in AWGN channels, compared to over 6.6 dB for RS-CC coding.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Lightweight hamming product code based multiple bit error correction coding s...journalBEEI
In this paper, we present multiple bit error correction coding scheme based on extended Hamming product code combined with type II HARQ using shared resources for on chip interconnect. The shared resources reduce the hardware complexity of the encoder and decoder compared to the existing three stages iterative decoding method for on chip interconnects. The proposed method of decoding achieves 20% and 28% reduction in area and power consumption respectively, with only small increase in decoder delay compared to the existing three stage iterative decoding scheme for multiple bit error correction. The proposed code also achieves excellent improvement in residual flit error rate and up to 58% of total power consumption compared to the other error control schemes. The low complexity and excellent residual flit error rate make the proposed code suitable for on chip interconnection links.
Performances Concatenated LDPC based STBC-OFDM System and MRC Receivers IJECEIAES
This document presents a study on the performance of a low density parity check (LDPC) coded orthogonal frequency division multiplexing (OFDM) system using space time block coding (STBC) under various digital modulations and channel conditions. The system incorporates a 3/4 rate convolutional encoder and a LDPC encoder. At the receiver, maximum ratio combining is implemented for channel equalization. Simulation results show that the LDPC coded OFDM system outperforms an uncoded system, and provides lower bit error rates under binary phase shift keying modulation in an additive white Gaussian noise channel.
This document describes interfacing a Controller Area Network (CAN) bus with a PIC32 microcontroller. It provides an overview of CAN bus, including its data format, signaling format, and features like message-based communication, arbitration, and error detection. The document then details the hardware design of the CAN bus system using a PIC32MX795F512L microcontroller and other components like transceivers, power supplies, and programming hardware.
Iterative network channel decoding with cooperative space-time transmissionijasuc
This document summarizes an iterative network-channel decoding scheme for cooperative space-time transmission with network coding. The scheme uses convolutional codes as network codes at the relay node and Reed-Solomon codes as channel codes at the user nodes. An iterative joint network-channel decoder exchanges soft information between convolutional code-based network decoder and Reed-Solomon code-based channel decoders. Extrinsic information transfer analysis is performed to investigate the convergence properties of the proposed iterative decoder.
Coverage of WCDMA Network Using Different Modulation Techniques with Soft and...ijcnac
The wideband code division multiple access (WCDMA) based 3G cellular mobile
wireless networks are expected to provide a diverse range of multimedia services to
mobile users with guaranteed quality of service (QoS). To serve diverse quality of service
requirements of these networks it necessitates new radio resource management strategies
for effective utilization of network resources with coding schemes. In this paper coverage
area for voice traffic and with different modulation techniques, coding schemes and
decision decoder are discussed. These discussions are to improve the coverage area in
the mobile communication system. This paper is mainly focuses on coverage area of
WCDMA system using link budget calculation with different modulation, coding schemes
and decision decoder. Simulation results demonstrate coverage extension for voice
service with different modulation,coding scheme, soft and hard decision decoder using
appropriate Bit error rate (BER) to maintain QoS of the voice.
PERFORMANCE EVALUATION OF CDMAROUTER FOR NETWORK - ON - CHIPVLSICS Design
This paper presents the performance evaluation of router based on code division multiple access technique (CDMA) for Network-on-Chip (NoC). The design is synthesized using Xilinx Virtex4 XC4VLX200 device. The functional behavior is verified using Modelsim XE III 6.2 C. The delay and throughput values are obtained for variable payload sizes. Throughput-Power and Delay-Power characteristics are also verified for NoC.
This document summarizes a research paper that proposes using parallel concatenated turbo codes in wireless sensor networks in an adaptive way. The key points are:
1) Turbo codes can achieve near-Shannon limit performance but decoding is complex, making them difficult to implement on energy-constrained sensor nodes.
2) The proposed approach shifts the complex turbo decoding to the base station while sensor nodes implement encoding and basic error correction.
3) At sensor nodes, a parallel concatenated convolutional code (PCCC) circuit encodes data and detects/corrects errors in forwarded packets. This improves energy efficiency and reliability over the wireless sensor network.
OPTICAL SWITCHING CONTROLLER USING FPGA AS A CONTROLLER FOR OCDMA ENCODER SYSTEMEditor IJCATR
This paper proposed a design of optical switching controller using FPGA for OCDMA encoder system. The encoder is one
of the new technologies that use to transmit the coded data in the optical communication system by using FPGA and optical switches.
It is providing a high security for data transmission due to all data will be transmitting in binary code form. The output signals from
FPGA are coded with a binary code that given to an optical switch before it signal modulate with the carrier and transmit to the
receiver. In this paper, AA and 55 data were used for source 1 and source 2. It is generated sample data and sent packet data to the
FPGA and stored it into RAM. The simulation results have done by using software Verilog Spartan 2 programming to simulate. After
that the output will produces at waveform to display the output. The main function of FPGA controlling unit is producing single pulse
and configuring optical switching system.
This document provides an overview of modern forward error correction (FEC) techniques used in satellite communications (SATCOM). It discusses the motivation for using FEC to combat various link impairments. It then reviews various FEC schemes including block codes, convolutional codes, turbo codes, and compares their performance. Turbo codes are shown to provide the best performance, approaching the theoretical Shannon limit, allowing for reduced transmitter power and bandwidth compared to older FEC schemes. The document concludes that while newer codes like turbo codes offer close to optimal performance, simpler block and convolutional codes also provide good performance for their lower complexity.
Effect of Interleaved FEC Code on Wavelet Based MC-CDMA System with Alamouti ...IJCSEIT Journal
In this paper, the impact of Forward Error Correction (FEC) code namely Trellis code with interleaver on
the performance of wavelet based MC-CDMA wireless communication system with the implementation of
Alamouti antenna diversity scheme has been investigated in terms of Bit Error Rate (BER) as a function of
Signal-to-Noise Ratio (SNR) per bit. Simulation of the system under proposed study has been done in M-ary
modulation schemes (MPSK, MQAM and DPSK) over AWGN and Rayleigh fading channel incorporating
Walsh Hadamard code as orthogonal spreading code to discriminate the message signal for individual
user. It is observed via computer simulation that the performance of the interleaved coded based proposed
system outperforms than that of the uncoded system in all modulation schemes over Rayleigh fading
channel.
DESIGN OF A COMPACT CIRCULAR MICROSTRIP PATCH ANTENNA FOR WLAN APPLICATIONS pijans
This paper presents the design of a compact circular microstrip patch antenna for WLAN applications which covers the band 5.15 to 5.825 GHz. The antenna is designed using 1.4mm thick FR-4 (lossy)substrate with relative permittivity 4.4 and a microstrip line feed is used. The radius of the circular patch is chosen as 7.62mm. To reduce the size and enhance the performance of the proposed antenna, a circular slot is loaded on circular patch and a square slot is etched on the ground plane of dimension 30mm×30mm. Design of the antenna is carried out using CST Microsoft Studio Sonimulation Software. The proposed antenna resonates at 5.5 GHz with a wider bandwidth of 702 MHz and it provides low return loss of -31.58 dB, good gain of 3.23 dB and directivity of 4.28 dBi and high efficiency of around 79% against the resonance frequency. The geometry of the proposed circular antenna with reduced size and its various performance parameters such as return loss, bandwidth, VSWR, gain, directivity, efficiency and radiation pattern plots are presented and discussed.
COMPARATIVE PERFORMANCE ASSESSMENT OF VBLAST ENCODED 8×8 MIMO MC-CDMA WIRELES...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN channel
and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission
IRJET- Performance Analysis of IP Over Optical CDMA System based on RD CodeIRJET Journal
This document presents a performance analysis of an IP over optical CDMA network system based on a random diagonal (RD) code. It proposes using spectral amplitude coding OCDMA to directly connect the IP layer to the optical layer, eliminating intermediate layers and reducing overhead. The system architecture, design steps, and simulation setup are described. Simulation results using OptiSystem show that bit error rate increases with the number of simultaneous users and data transmission capacity decreases with transmission distance as expected. The RD code OCDMA system provides a potential solution for next-generation networks by enabling intelligent functions and advanced services at the optical layer.
VTU 8TH SEM CSE ADHOC NETWORKS SOLVED PAPERS OF JUNE-2014 DEC-14 & JUNE-2015vtunotesbysree
The document discusses solved papers from past exams on ad hoc networks. It includes answers to multiple choice and descriptive questions covering topics such as wireless mesh networks, hybrid wireless networks, issues in designing ad hoc wireless internet, MAC protocol design considerations including QoS and hidden node problems, and routing protocols for ad hoc networks including CGSR and ZRP. Diagrams and detailed explanations are provided for many of the concepts and protocols discussed.
Performance analysis of negative group delay network using MIMO techniqueTELKOMNIKA JOURNAL
This study introduces comparative consequences that determine the bit error rate enhancements, resultant from adopting a proposed MIMO wireless model in this study. The antenna configurations for this model uses new small microstrip slotted patch antenna with multiple frequency bands at strategic operating frequencies of 2.4, 4.4, and 5.55 respectively. The S11 response of the proposed antenna for IEEE802.11 MIMO wireless network has been highly appropriate to be adopted with MIMO antenna system. The negative group delay (NGD) response is the most significant feature for projected MIMO antenna. The NGD stands for a counterintuitive singularity that interacts time advancement with wave propagation. These improvements are employed for increasing a reliability of instantly conveyed data streams, enhance the capacity of the wireless configuration and decrease the bit error rate (BER) of adopted wireless system. In addition to antenna scattering response, the enhancements have been analysed in term of BER for different MIMO topologies.
Comparative Performance Assessment of V-Blast Encoded 8×8 MIMO MC-CDMA Wirele...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN
channel and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission
SECURED TEXT MESSAGE TRANSMISSION WITH IMPLEMENTATION OF CONCATENATED CFB CRY...cscpconf
In the present simulated system, text message transmission has been secured with concatenated
implementation of Cipher Feedback(CFB) cryptographic algorithm. It is anticipated from the numerical
results that the pre-ZF channel equalization based MIMO OFDM wireless communication
system outperforms in QAM digital modulation and BCH channel coding under AWGN and
Raleigh fading channels .In Pre-MMSE/pre-ZF channel equalization scheme, the system shows
comparatively worst performance in convolutional channel coding scheme with QAM/QPSK digital
modulation. It has been observed from the present study that the system performance deteriorates with
increase in noise power as compared to signal power. study of a secured MIMO Orthogonal
Frequency-Division Multiplexing wireless communication system with implementation of two pre
channel equalization techniques such as Pre-Minimum Mean Square Error (Pre-MMSE) and PreZero
Forcing(Pre-ZF) under QPSK and QAM digital modulations.
Equalization & Channel Estimation of Block & Comb Type CodesAM Publications
Multi-carrier code division multiple access is an attractive choice for high speed wireless communication as it mitigates
the problem of inter symbol interference and also exploits frequency diversity. The work described in this paper is my effort in this
direction. In this paper working of Transmitter and Receiver model of MCCDMA system is presented. We evaluated interference
and bit error rate for multicarrier code division multiple access wireless communication system. In this thesis my concern is find
out the effect of interference in MC-CDMA system. We find out the effect of number of users and signal power on different
parameters for MC-CDMA system. Simulations are given to support the system and receiver design. All the simulation is carried out on MATLAB tool.
Implementation of Joint Network Channel Decoding Algorithm for Multiple Acces...csandit
In this paper, we consider a Joint Network Channel Decoding (JNCD) algorithm applied to a
wireless network consisting to M users. For this purpose M sources desire to send information
to one receiver by the help of an intermediate node which is the relay. The Physical Layer
Network Coding (PLNC) allows the relay to decode the combined information being sent from
different transmitters. Then, it forwards additional information to the destination node which
receives also signals from source nodes. An iterative JNCD algorithm is developed at the
receiver to estimate the information being sent from each transmitter. Simulation results show
that the Bit Error Rate (BER) can be decreased by using this concept comparing to the
reference one which doesn’t consider the network coding.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Rs(n,k)exploring n and k in reed solomon fec codeMapYourTech
The document discusses Reed-Solomon FEC coding. It explains that Reed-Solomon RS(n,k) encoding takes k data bytes and calculates n-k parity bytes to create an n-byte codeword. A Reed-Solomon decoder can correct up to t byte errors, where t=(n-k)/2. ITU G.975 and G.709 recommend Reed-Solomon RS(255,239) coding, which can correct up to 8 byte errors and provides a coding gain of around 6dB with a 7% overhead. The document also provides examples of calculating RS(n,k) parameters for an OTN frame.
Performances Concatenated LDPC based STBC-OFDM System and MRC Receivers IJECEIAES
This document presents a study on the performance of a low density parity check (LDPC) coded orthogonal frequency division multiplexing (OFDM) system using space time block coding (STBC) under various digital modulations and channel conditions. The system incorporates a 3/4 rate convolutional encoder and a LDPC encoder. At the receiver, maximum ratio combining is implemented for channel equalization. Simulation results show that the LDPC coded OFDM system outperforms an uncoded system, and provides lower bit error rates under binary phase shift keying modulation in an additive white Gaussian noise channel.
This document describes interfacing a Controller Area Network (CAN) bus with a PIC32 microcontroller. It provides an overview of CAN bus, including its data format, signaling format, and features like message-based communication, arbitration, and error detection. The document then details the hardware design of the CAN bus system using a PIC32MX795F512L microcontroller and other components like transceivers, power supplies, and programming hardware.
Iterative network channel decoding with cooperative space-time transmissionijasuc
This document summarizes an iterative network-channel decoding scheme for cooperative space-time transmission with network coding. The scheme uses convolutional codes as network codes at the relay node and Reed-Solomon codes as channel codes at the user nodes. An iterative joint network-channel decoder exchanges soft information between convolutional code-based network decoder and Reed-Solomon code-based channel decoders. Extrinsic information transfer analysis is performed to investigate the convergence properties of the proposed iterative decoder.
Coverage of WCDMA Network Using Different Modulation Techniques with Soft and...ijcnac
The wideband code division multiple access (WCDMA) based 3G cellular mobile
wireless networks are expected to provide a diverse range of multimedia services to
mobile users with guaranteed quality of service (QoS). To serve diverse quality of service
requirements of these networks it necessitates new radio resource management strategies
for effective utilization of network resources with coding schemes. In this paper coverage
area for voice traffic and with different modulation techniques, coding schemes and
decision decoder are discussed. These discussions are to improve the coverage area in
the mobile communication system. This paper is mainly focuses on coverage area of
WCDMA system using link budget calculation with different modulation, coding schemes
and decision decoder. Simulation results demonstrate coverage extension for voice
service with different modulation,coding scheme, soft and hard decision decoder using
appropriate Bit error rate (BER) to maintain QoS of the voice.
PERFORMANCE EVALUATION OF CDMAROUTER FOR NETWORK - ON - CHIPVLSICS Design
This paper presents the performance evaluation of router based on code division multiple access technique (CDMA) for Network-on-Chip (NoC). The design is synthesized using Xilinx Virtex4 XC4VLX200 device. The functional behavior is verified using Modelsim XE III 6.2 C. The delay and throughput values are obtained for variable payload sizes. Throughput-Power and Delay-Power characteristics are also verified for NoC.
This document summarizes a research paper that proposes using parallel concatenated turbo codes in wireless sensor networks in an adaptive way. The key points are:
1) Turbo codes can achieve near-Shannon limit performance but decoding is complex, making them difficult to implement on energy-constrained sensor nodes.
2) The proposed approach shifts the complex turbo decoding to the base station while sensor nodes implement encoding and basic error correction.
3) At sensor nodes, a parallel concatenated convolutional code (PCCC) circuit encodes data and detects/corrects errors in forwarded packets. This improves energy efficiency and reliability over the wireless sensor network.
OPTICAL SWITCHING CONTROLLER USING FPGA AS A CONTROLLER FOR OCDMA ENCODER SYSTEMEditor IJCATR
This paper proposed a design of optical switching controller using FPGA for OCDMA encoder system. The encoder is one
of the new technologies that use to transmit the coded data in the optical communication system by using FPGA and optical switches.
It is providing a high security for data transmission due to all data will be transmitting in binary code form. The output signals from
FPGA are coded with a binary code that given to an optical switch before it signal modulate with the carrier and transmit to the
receiver. In this paper, AA and 55 data were used for source 1 and source 2. It is generated sample data and sent packet data to the
FPGA and stored it into RAM. The simulation results have done by using software Verilog Spartan 2 programming to simulate. After
that the output will produces at waveform to display the output. The main function of FPGA controlling unit is producing single pulse
and configuring optical switching system.
This document provides an overview of modern forward error correction (FEC) techniques used in satellite communications (SATCOM). It discusses the motivation for using FEC to combat various link impairments. It then reviews various FEC schemes including block codes, convolutional codes, turbo codes, and compares their performance. Turbo codes are shown to provide the best performance, approaching the theoretical Shannon limit, allowing for reduced transmitter power and bandwidth compared to older FEC schemes. The document concludes that while newer codes like turbo codes offer close to optimal performance, simpler block and convolutional codes also provide good performance for their lower complexity.
Effect of Interleaved FEC Code on Wavelet Based MC-CDMA System with Alamouti ...IJCSEIT Journal
In this paper, the impact of Forward Error Correction (FEC) code namely Trellis code with interleaver on
the performance of wavelet based MC-CDMA wireless communication system with the implementation of
Alamouti antenna diversity scheme has been investigated in terms of Bit Error Rate (BER) as a function of
Signal-to-Noise Ratio (SNR) per bit. Simulation of the system under proposed study has been done in M-ary
modulation schemes (MPSK, MQAM and DPSK) over AWGN and Rayleigh fading channel incorporating
Walsh Hadamard code as orthogonal spreading code to discriminate the message signal for individual
user. It is observed via computer simulation that the performance of the interleaved coded based proposed
system outperforms than that of the uncoded system in all modulation schemes over Rayleigh fading
channel.
DESIGN OF A COMPACT CIRCULAR MICROSTRIP PATCH ANTENNA FOR WLAN APPLICATIONS pijans
This paper presents the design of a compact circular microstrip patch antenna for WLAN applications which covers the band 5.15 to 5.825 GHz. The antenna is designed using 1.4mm thick FR-4 (lossy)substrate with relative permittivity 4.4 and a microstrip line feed is used. The radius of the circular patch is chosen as 7.62mm. To reduce the size and enhance the performance of the proposed antenna, a circular slot is loaded on circular patch and a square slot is etched on the ground plane of dimension 30mm×30mm. Design of the antenna is carried out using CST Microsoft Studio Sonimulation Software. The proposed antenna resonates at 5.5 GHz with a wider bandwidth of 702 MHz and it provides low return loss of -31.58 dB, good gain of 3.23 dB and directivity of 4.28 dBi and high efficiency of around 79% against the resonance frequency. The geometry of the proposed circular antenna with reduced size and its various performance parameters such as return loss, bandwidth, VSWR, gain, directivity, efficiency and radiation pattern plots are presented and discussed.
COMPARATIVE PERFORMANCE ASSESSMENT OF VBLAST ENCODED 8×8 MIMO MC-CDMA WIRELES...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN channel
and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission
IRJET- Performance Analysis of IP Over Optical CDMA System based on RD CodeIRJET Journal
This document presents a performance analysis of an IP over optical CDMA network system based on a random diagonal (RD) code. It proposes using spectral amplitude coding OCDMA to directly connect the IP layer to the optical layer, eliminating intermediate layers and reducing overhead. The system architecture, design steps, and simulation setup are described. Simulation results using OptiSystem show that bit error rate increases with the number of simultaneous users and data transmission capacity decreases with transmission distance as expected. The RD code OCDMA system provides a potential solution for next-generation networks by enabling intelligent functions and advanced services at the optical layer.
VTU 8TH SEM CSE ADHOC NETWORKS SOLVED PAPERS OF JUNE-2014 DEC-14 & JUNE-2015vtunotesbysree
The document discusses solved papers from past exams on ad hoc networks. It includes answers to multiple choice and descriptive questions covering topics such as wireless mesh networks, hybrid wireless networks, issues in designing ad hoc wireless internet, MAC protocol design considerations including QoS and hidden node problems, and routing protocols for ad hoc networks including CGSR and ZRP. Diagrams and detailed explanations are provided for many of the concepts and protocols discussed.
Performance analysis of negative group delay network using MIMO techniqueTELKOMNIKA JOURNAL
This study introduces comparative consequences that determine the bit error rate enhancements, resultant from adopting a proposed MIMO wireless model in this study. The antenna configurations for this model uses new small microstrip slotted patch antenna with multiple frequency bands at strategic operating frequencies of 2.4, 4.4, and 5.55 respectively. The S11 response of the proposed antenna for IEEE802.11 MIMO wireless network has been highly appropriate to be adopted with MIMO antenna system. The negative group delay (NGD) response is the most significant feature for projected MIMO antenna. The NGD stands for a counterintuitive singularity that interacts time advancement with wave propagation. These improvements are employed for increasing a reliability of instantly conveyed data streams, enhance the capacity of the wireless configuration and decrease the bit error rate (BER) of adopted wireless system. In addition to antenna scattering response, the enhancements have been analysed in term of BER for different MIMO topologies.
Comparative Performance Assessment of V-Blast Encoded 8×8 MIMO MC-CDMA Wirele...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN
channel and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission
SECURED TEXT MESSAGE TRANSMISSION WITH IMPLEMENTATION OF CONCATENATED CFB CRY...cscpconf
In the present simulated system, text message transmission has been secured with concatenated
implementation of Cipher Feedback(CFB) cryptographic algorithm. It is anticipated from the numerical
results that the pre-ZF channel equalization based MIMO OFDM wireless communication
system outperforms in QAM digital modulation and BCH channel coding under AWGN and
Raleigh fading channels .In Pre-MMSE/pre-ZF channel equalization scheme, the system shows
comparatively worst performance in convolutional channel coding scheme with QAM/QPSK digital
modulation. It has been observed from the present study that the system performance deteriorates with
increase in noise power as compared to signal power. study of a secured MIMO Orthogonal
Frequency-Division Multiplexing wireless communication system with implementation of two pre
channel equalization techniques such as Pre-Minimum Mean Square Error (Pre-MMSE) and PreZero
Forcing(Pre-ZF) under QPSK and QAM digital modulations.
Equalization & Channel Estimation of Block & Comb Type CodesAM Publications
Multi-carrier code division multiple access is an attractive choice for high speed wireless communication as it mitigates
the problem of inter symbol interference and also exploits frequency diversity. The work described in this paper is my effort in this
direction. In this paper working of Transmitter and Receiver model of MCCDMA system is presented. We evaluated interference
and bit error rate for multicarrier code division multiple access wireless communication system. In this thesis my concern is find
out the effect of interference in MC-CDMA system. We find out the effect of number of users and signal power on different
parameters for MC-CDMA system. Simulations are given to support the system and receiver design. All the simulation is carried out on MATLAB tool.
Implementation of Joint Network Channel Decoding Algorithm for Multiple Acces...csandit
In this paper, we consider a Joint Network Channel Decoding (JNCD) algorithm applied to a
wireless network consisting to M users. For this purpose M sources desire to send information
to one receiver by the help of an intermediate node which is the relay. The Physical Layer
Network Coding (PLNC) allows the relay to decode the combined information being sent from
different transmitters. Then, it forwards additional information to the destination node which
receives also signals from source nodes. An iterative JNCD algorithm is developed at the
receiver to estimate the information being sent from each transmitter. Simulation results show
that the Bit Error Rate (BER) can be decreased by using this concept comparing to the
reference one which doesn’t consider the network coding.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Rs(n,k)exploring n and k in reed solomon fec codeMapYourTech
The document discusses Reed-Solomon FEC coding. It explains that Reed-Solomon RS(n,k) encoding takes k data bytes and calculates n-k parity bytes to create an n-byte codeword. A Reed-Solomon decoder can correct up to t byte errors, where t=(n-k)/2. ITU G.975 and G.709 recommend Reed-Solomon RS(255,239) coding, which can correct up to 8 byte errors and provides a coding gain of around 6dB with a 7% overhead. The document also provides examples of calculating RS(n,k) parameters for an OTN frame.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
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yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Tietojärjestelmien hankinnasta vallalla oleva yleinen mielikuva on, että rahaa palaa ja valmista ei tule. Onko tilanne todellakin näin huono, kuin annetaan ymmärtää, vai onko uutisointi tarkoitushakuista ja pintaa syvemmällä asiat hoituvat kuitenkin normaalisti? Tähän asiaan pyrkii tuomaan selvyyttä Celkee Oy:n, Tietotekniikan liitto ry:n ja Ohjelmistoyrittäjät ry:n yhteistyössä julkaisema valtakunnallinen Tietojärjestelmien hankinta Suomessa -tutkimus, joka toteutettiin nyt
ensimmäistä kertaa.
This membership card belongs to Robert Pusey and provides his member ID and dates of membership. It lists contact information for the Society for Human Resource Management's member care center and HR knowledge center. The card notes that SHRM is an individual membership organization and this card is not to be shared with others.
Andrew Mann has experience managing design and construction projects for MAN Truck & Bus UK Ltd dealerships across the UK. His responsibilities included site selection, managing design teams and contractors, and liaising with local authorities for approvals. He oversaw projects such as a new dealership built on a sensitive wetlands site in Newport, the redevelopment of a listed building in Enfield, and construction of a new facility in Irlam.
Convolutional encoding with Viterbi decoding is a good forward error correction technique suitable for channels affected by noise degradation. Fangled Viterbi decoders are variants of Viterbi decoder (VD) which decodes quicker and takes less memory with no error detection capability. Modified fangled takes it a step further by gaining one bit error correction and detection capability at the cost of doubling the computational complexity and processing time. A new efficient fangled Viterbi algorithm is proposed in this paper with less complexity and processing time along with 2 bit error correction capabilities. For 1 bit error correction for 14 bit input data, when compared with Modified fangled Viterbi decoder, computational complexity has come down by 36-43% and processing delay was halved. For a 2 bit error correction, when compared with Modified fangled decoder computational complexity decreased by 22-36%.
FPGA Implementation of Viterbi Decoder using Hybrid Trace Back and Register E...ijsrd.com
Error correction is an integral part of any communication system and for this purpose, the convolution codes are widely used as forward error correction codes. For decoding of convolution codes, at the receiver end Viterbi Decoder is being employed. The parameters of Viterbi algorithm can be changed to suit a specific application. The high speed and small area are two important design parameters in today’s wireless technology. In this paper, a high speed feed forward viterbi decoder has been designed using hybrid track back and register exchange architecture and embedded BRAM of target FPGA. The proposed viterbi decoder has been designed with Matlab, simulated with Xilinx ISE 8.1i Tool, synthesized with Xilinx Synthesis Tool (XST), and implemented on Xilinx Virtex4 based xc4vlx15 FPGA device. The results show that the proposed design can operate at an estimated frequency of 107.7 MHz by consuming considerably less resources on target device to provide cost effective solution for wireless applications.
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
This document describes the implementation of a Viterbi decoder using VHDL. It begins with background on convolutional encoding, the Viterbi algorithm for decoding convolutional codes, and the basic structure of a Viterbi decoder. It then discusses the design and simulation of a rate 1/2 constraint length 3 Viterbi decoder in VHDL targeting the Spartan-3A FPGA. Simulation results and comparisons to other FPGA devices are presented.
Implementation of Viterbi Decoder on FPGA to Improve Designijsrd.com
This document discusses the implementation of a Viterbi decoder on an FPGA to improve its design. It begins with an introduction to convolutional encoding and the Viterbi algorithm. It then describes the basic components of a Viterbi decoder including the branch metric unit, path metric unit, and survivor memory management unit. It discusses different techniques for Viterbi decoding including hard decision, soft decision, and various register exchange methods. It concludes that increasing the constraint length improves the decoder's performance and that traceback methods are more area efficient than register exchange methods for large constraint lengths.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document discusses the design of an asynchronous Viterbi decoder using a bundled data protocol to reduce power consumption. Viterbi decoders are commonly used in wireless communications and other applications, but synchronous implementations consume significant power due to global clock distribution. The proposed asynchronous design uses local handshaking signals between blocks rather than a global clock. It employs a 4-phase bundled data protocol to communicate data between units like the branch metric unit, add-compare-select unit, and survivor path memory unit. The goal is to optimize these power-intensive units and achieve lower power operation through an asynchronous, clock-free design approach compared to traditional synchronous Viterbi decoders.
FPGA Implementation of Efficient Viterbi Decoder for Multi-Carrier SystemsIJMER
In this paper, we concern with designing and implementing a Convolutional encoder and
Adaptive Viterbi Decoder (AVD) which are the essential blocks in digital communication system using
FPGA technology. Convolutional coding is a coding scheme used in communication systems for error
correction employed in applications like deep space communications and wireless communications. It
provides an alternative approach to block codes for transmission over a noisy channel. The block
codes can be applied only for the blocks of data where as the Convolutional coding has an advantage
that it can be applied to both continuous data stream and blocks of data. The Viterbi decoder with
PNPH (Permutation Network based Path History) management unit which is a special path
management unit for faster decoding speed with less routing area. The proposed architecture can be
realized by an Adaptive Viterbi Decoder having constraint length, K of 3 and a code rate (k/n) of 1/2
using Verilog HDL. Simulation is done using Xilinx ISE 12.4i design software and it is targeted into
Xilinx Virtex-5, XC5VLX110T FPGA
High Speed Low-Power Viterbi Decoder Using Trellis Code ModulationMangaiK4
Abstract - High speed low power viterbi decoders for trellis code modulation is well known for the delay consumption in underwater communication. In transmission system wireless communication is the transfer of information between two or more points that are not connected by an electrical conductor. WiMAX is the wireless communication standard designed to provide 30 to 40 Mega bits per second data rates. WiMAX as a standards based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL. WiMAX can provide at home or mobile internet access across whole cities or countries. The address generation of WiMAX is carried out by interleaver and deinterleaver. Interleaving is used to overcome correlated channel noise such as burst error or fading. The interleaver/deinterleaver rearranges input data such that consecutive data are spaced apart. The interleaved memory is to improve the speed of access to memory. The viterbi technique reduces the bit error rate and delay using wimax.
High Speed Low-Power Viterbi Decoder Using Trellis Code ModulationMangaiK4
Abstract - High speed low power viterbi decoders for trellis code modulation is well known for the delay consumption in underwater communication. In transmission system wireless communication is the transfer of information between two or more points that are not connected by an electrical conductor. WiMAX is the wireless communication standard designed to provide 30 to 40 Mega bits per second data rates. WiMAX as a standards based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL. WiMAX can provide at home or mobile internet access across whole cities or countries. The address generation of WiMAX is carried out by interleaver and deinterleaver. Interleaving is used to overcome correlated channel noise such as burst error or fading. The interleaver/deinterleaver rearranges input data such that consecutive data are spaced apart. The interleaved memory is to improve the speed of access to memory. The viterbi technique reduces the bit error rate and delay using wimax.
A 2 stage data word packet communication decoder using rate 1-by-3 viterbi de...eSAT Journals
Abstract
In the field of consumer electronics the high speed communication technology applications based on hardware and software control are playing a vital role in establishing the benchmarks for catering the operational requirements of the electronic hardware to fulfil the consumer requirements in wired and wireless communication. In the modern era of communication electronics decoding and encoding of any data(s) using high speed and low power features of FPGA devices [1] based on VLSI technology offers less area, hardware portability, data security, high speed network connectivity [2], data error removal capability, complex algorithm realization, etc. Viterbi decoder is a high rate decoder that is very commonly and effectively used method in modern communication hardware. It involves Trellis coded modulation (TCM) scheme for decoding the data. The viterbi decoder is an attempt to reduce the power, speed [1], and cost as compared to normal decoders for wired and wireless communication. The work in this paper proposes a improved data error identification probability design of Viterbi decoders for communication systems with a low power operational performance. The proposed design combines the error identification capability of the viterbi decoder with parity decoder to improve the probability of the overall system in identifying the error during the communication process. Among various functional blocks in the Viterbi decoder, both hardware complexity and decoding speed highly depends on the architecture of the Decoder. The operational blocks of viterbi decoder are combined with parity testing block to identify the error in the viterbi decoded data using parity bit. The present design proposes a multi-stage pipelined architecture of decoder. The former stage is the viterbi decoding stage and the later stage is the parity decoding stage for the identification of error in the communicated data. Any Odd number of errors occuring in the recovered data from the former decoding stage can be identified using the later decoding stage. A general solution to derive the communication using conventional viterbi decoder is also given in this paper. Implementation result of proposed design for a rate 1/3 convolutional code is compared with the conventional design. The design of proposed algorithm is simulated and synthesized successfully Xilinx ISE Tool [3] on Xilinx Spartan 3E FPGA.
Keywords: ACS (Add-Compare-Select), Convolutional Code Rate, Error probability, FPGA, Low Power, Parity Encoder, Pipelining, Trace Back, Viterbi Decoder, Xilinx ISE.
Turbo codes are error-correcting codes with performance that is close to the
Shannon theoretical limit (SHA). The motivation for using turbo codes is
that the codes are an appealing mix of a random appearance on the channel
and a physically realizable decoding structure. The communication systems
have the problem of latency, fast switching, and reliable data transfer. The
objective of the research paper is to design and turbo encoder and decoder
hardware chip and analyze its performance. Two convolutional codes are
concatenated concurrently and detached by an interleaver or permuter in the
turbo encoder. The expected data from the channel is interpreted iteratively
using the two related decoders. The soft (probabilistic) data about an
individual bit of the decoded structure is passed in each cycle from one
elementary decoder to the next, and this information is updated regularly.
The performance of the chip is also verified using the maximum a posteriori
(MAP) method in the decoder chip. The performance of field-programmable
gate array (FPGA) hardware is evaluated using hardware and timing
parameters extracted from Xilinx ISE 14.7. The parallel concatenation offers
a better global rate for the same component code performance, and reduced
delay, low hardware complexity, and higher frequency support.
Design of High Speed and Low Power Veterbi Decoder for Trellis Coded Modulati...ijsrd.com
It is well known that the Viterbi decoder (VD) is the dominant module determining the overall power consumption of TCM decoders. High-speed, low-power design of Viterbi decoders for trellis coded modulation (TCM) systems is presented in this paper. We propose a pre-computation architecture incorporated with -algorithm for VD, which can effectively reduce the power consumption without degrading the decoding speed much. A general solution to derive the optimal pre-computation steps is also given in the paper. Implementation result of a VD for a rate-3/4 convolutional code used in a TCM system shows that compared with the full trellis VD, the precomputation architecture reduces the power consumption by as much as 70% without performance loss, while the degradation in clock speed is negligible.
Iaetsd vlsi implementation of efficient convolutionalIaetsd Iaetsd
This document describes the implementation of an efficient convolutional encoder and modified Viterbi decoder using FPGA technology. It begins with an introduction to convolutional encoding and Viterbi decoding. It then discusses the implementation of a convolutional encoder, including the state diagram and state table. Next, it describes the Viterbi algorithm and its components: branch metric calculation, path metric calculation using an add-compare-select unit, and traceback. It introduces the modified Viterbi algorithm and how it reduces computations and path storage requirements. It presents the design of the convolutional encoder and modified Viterbi decoder in Verilog HDL. Finally, it shows simulation results of the convolutional encoder and components of the modified Viterbi decoder.
This document presents research on implementing CRC and Viterbi error correction techniques on a DSP processor. CRC-32 and Viterbi decoding algorithms for convolutional codes with rate 1/2 and different generator polynomials are simulated and implemented on a TMS320C5416 DSP chip. Additionally, a concept of serially concatenated CRC-convolutional coding is proposed, using a lookup table at the decoder to potentially reduce computations compared to traditional Viterbi decoding. Simulation results demonstrating CRC-8, CRC-32, and Viterbi decoding with various generator polynomials and error scenarios are shown. The techniques are successfully implemented on the DSP hardware.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
For wireless communication, the demand for high speed, low power and low cost Viterbi decoding are always required. Convolutional coding with Viterbi decoding is a very powerful method for forward error correction and detection method. It has been popularly used in many wireless communication systems to improve the limited capacity of its communication channels. VLSI technology in advance is using low power, less area and high speed constraints is often used for encoding and decoding of data.
Viterbi Decoder Plain Sailing Design for TCM Decodersijtsrd
Convolutional codes are error correction technique used in noisy channels. Viterbi Algorithm is the most widely used decoding Algorithm, which decodes the sequence in a maximum likelihood sense. But the complexity of the Viterbi decoder increases with the coding rate of the system. Viterbi decoder is the most power hungry module in the Trellis coded modulation system. Viterbi decoding is the best technique for decoding the convolutional codes but it is limited to smaller constraint lengths. The basic building blocks of Viterbi decoder are branch metric unit, add compare and select unit and survivor memory management unit. From the simulation results it is observed that the proposed Viterbi decoder architecture with modified Branch metric calculation can reduce significant amount of computations in order to decrease the hardware usage and to simplify the proceedings. Suman Chandel | Manju Mathur "Viterbi Decoder Plain Sailing Design for TCM Decoders" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26710.pdf Paper URL: https://www.ijtsrd.com/engineering/electronics-and-communication-engineering/26710/viterbi-decoder-plain-sailing-design-for-tcm-decoders/suman-chandel
Estimation and design of mc ds-cdma for hybrid concatenated coding in high sp...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Estimation and design of mc ds-cdma for hybrid concatenated coding in high sp...eSAT Journals
Abstract The design of Multi Carrier Direct Sequence Code Division Multiple Access (MC-DS-CDMA) structure which generalizes serial and parallel concatenated code is investigated to this project. This model is ideal for designing various codes in the performance of both error floor and water floor region. We propose a concatenated code for transmitter block which is used for multi carrier direct sequence CDMA technique. Simulation results of MC-DS-CDMA uplink system using Cadence software shows the various parameters such as memory, Execution time and number of transient steps required for the Execution of MC-DS-CDMA uplink system was estimated and also power consumed was determined for each block in the transmitter. An improved concatenated code model is used for uplink mobile communication. Further system performance improvements can be obtained by concatenating inner code and outer code and the results of computer simulations demonstrate that the performance of the concatenated code was investigated. Keywords: Code Division Multiple Access, Concatenated code, inner code, outer code, interleaving and power analysis.
Similar to International Journal of Engineering Research and Development (IJERD) (20)
A Novel Method for Prevention of Bandwidth Distributed Denial of Service AttacksIJERD Editor
Distributed Denial of Service (DDoS) Attacks became a massive threat to the Internet. Traditional
Architecture of internet is vulnerable to the attacks like DDoS. Attacker primarily acquire his army of Zombies,
then that army will be instructed by the Attacker that when to start an attack and on whom the attack should be
done. In this paper, different techniques which are used to perform DDoS Attacks, Tools that were used to
perform Attacks and Countermeasures in order to detect the attackers and eliminate the Bandwidth Distributed
Denial of Service attacks (B-DDoS) are reviewed. DDoS Attacks were done by using various Flooding
techniques which are used in DDoS attack.
The main purpose of this paper is to design an architecture which can reduce the Bandwidth
Distributed Denial of service Attack and make the victim site or server available for the normal users by
eliminating the zombie machines. Our Primary focus of this paper is to dispute how normal machines are
turning into zombies (Bots), how attack is been initiated, DDoS attack procedure and how an organization can
save their server from being a DDoS victim. In order to present this we implemented a simulated environment
with Cisco switches, Routers, Firewall, some virtual machines and some Attack tools to display a real DDoS
attack. By using Time scheduling, Resource Limiting, System log, Access Control List and some Modular
policy Framework we stopped the attack and identified the Attacker (Bot) machines
Hearing loss is one of the most common human impairments. It is estimated that by year 2015 more
than 700 million people will suffer mild deafness. Most can be helped by hearing aid devices depending on the
severity of their hearing loss. This paper describes the implementation and characterization details of a dual
channel transmitter front end (TFE) for digital hearing aid (DHA) applications that use novel micro
electromechanical- systems (MEMS) audio transducers and ultra-low power-scalable analog-to-digital
converters (ADCs), which enable a very-low form factor, energy-efficient implementation for next-generation
DHA. The contribution of the design is the implementation of the dual channel MEMS microphones and powerscalable
ADC system.
Influence of tensile behaviour of slab on the structural Behaviour of shear c...IJERD Editor
-A composite beam is composed of a steel beam and a slab connected by means of shear connectors
like studs installed on the top flange of the steel beam to form a structure behaving monolithically. This study
analyzes the effects of the tensile behavior of the slab on the structural behavior of the shear connection like slip
stiffness and maximum shear force in composite beams subjected to hogging moment. The results show that the
shear studs located in the crack-concentration zones due to large hogging moments sustain significantly smaller
shear force and slip stiffness than the other zones. Moreover, the reduction of the slip stiffness in the shear
connection appears also to be closely related to the change in the tensile strain of rebar according to the increase
of the load. Further experimental and analytical studies shall be conducted considering variables such as the
reinforcement ratio and the arrangement of shear connectors to achieve efficient design of the shear connection
in composite beams subjected to hogging moment.
Gold prospecting using Remote Sensing ‘A case study of Sudan’IJERD Editor
Gold has been extracted from northeast Africa for more than 5000 years, and this may be the first
place where the metal was extracted. The Arabian-Nubian Shield (ANS) is an exposure of Precambrian
crystalline rocks on the flanks of the Red Sea. The crystalline rocks are mostly Neoproterozoic in age. ANS
includes the nations of Israel, Jordan. Egypt, Saudi Arabia, Sudan, Eritrea, Ethiopia, Yemen, and Somalia.
Arabian Nubian Shield Consists of juvenile continental crest that formed between 900 550 Ma, when intra
oceanic arc welded together along ophiolite decorated arc. Primary Au mineralization probably developed in
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have obscured the primary metallogenic setting, but at least some of the deposits preserve evidence that they
originate as sea floor massive sulphide deposits.
The Red Sea Hills Region is a vast span of rugged, harsh and inhospitable sector of the Earth with
inimical moon-like terrain, nevertheless since ancient times it is famed to be an abode of gold and was a major
source of wealth for the Pharaohs of ancient Egypt. The Pharaohs old workings have been periodically
rediscovered through time. Recent endeavours by the Geological Research Authority of Sudan led to the
discovery of a score of occurrences with gold and massive sulphide mineralizations. In the nineties of the
previous century the Geological Research Authority of Sudan (GRAS) in cooperation with BRGM utilized
satellite data of Landsat TM using spectral ratio technique to map possible mineralized zones in the Red Sea
Hills of Sudan. The outcome of the study mapped a gossan type gold mineralization. Band ratio technique was
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associated with mineralization. The alteration zones are commonly associated with mineralization. A filed check
confirmed the existence of stock work of gold bearing quartz in the alteration zone. Another type of gold
mineralization that was discovered using remote sensing is the gold associated with metachert in the Atmur
Desert.
Reducing Corrosion Rate by Welding DesignIJERD Editor
This document summarizes a study on reducing corrosion rates in steel through welding design. The researchers tested different welding groove designs (X, V, 1/2X, 1/2V) and preheating temperatures (400°C, 500°C, 600°C) on ferritic malleable iron samples. Testing found that X and V groove designs with 500°C and 600°C preheating had corrosion rates of 0.5-0.69% weight loss after 14 days, compared to 0.57-0.76% for 400°C preheating. Higher preheating reduced residual stresses which decreased corrosion. Residual stresses were 1.7 MPa for optimal X groove and 600°C
Router 1X3 – RTL Design and VerificationIJERD Editor
Routing is the process of moving a packet of data from source to destination and enables messages
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Active Power Exchange in Distributed Power-Flow Controller (DPFC) At Third Ha...IJERD Editor
This paper presents a component within the flexible ac-transmission system (FACTS) family, called
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between the shunt and series converters, which is through the common dc link in the UPFC, is now through the
transmission lines at the third-harmonic frequency. DPFC multiple small-size single-phase converters which
reduces the cost of equipment, no voltage isolation between phases, increases redundancy and there by
reliability increases. The principle and analysis of the DPFC are presented in this paper and the corresponding
simulation results that are carried out on a scaled prototype are also shown.
Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVRIJERD Editor
Power quality has been an issue that is becoming increasingly pivotal in industrial electricity
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Study on the Fused Deposition Modelling In Additive ManufacturingIJERD Editor
Additive manufacturing process, also popularly known as 3-D printing, is a process where a product
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Spyware triggering system by particular string valueIJERD Editor
This computer programme can be used for good and bad purpose in hacking or in any general
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A Blind Steganalysis on JPEG Gray Level Image Based on Statistical Features a...IJERD Editor
This paper presents a blind steganalysis technique to effectively attack the JPEG steganographic
schemes i.e. Jsteg, F5, Outguess and DWT Based. The proposed method exploits the correlations between
block-DCTcoefficients from intra-block and inter-block relation and the statistical moments of characteristic
functions of the test image is selected as features. The features are extracted from the BDCT JPEG 2-array.
Support Vector Machine with cross-validation is implemented for the classification.The proposed scheme gives
improved outcome in attacking.
Secure Image Transmission for Cloud Storage System Using Hybrid SchemeIJERD Editor
- Data over the cloud is transferred or transmitted between servers and users. Privacy of that
data is very important as it belongs to personal information. If data get hacked by the hacker, can be
used to defame a person’s social data. Sometimes delay are held during data transmission. i.e. Mobile
communication, bandwidth is low. Hence compression algorithms are proposed for fast and efficient
transmission, encryption is used for security purposes and blurring is used by providing additional
layers of security. These algorithms are hybridized for having a robust and efficient security and
transmission over cloud storage system.
Application of Buckley-Leverett Equation in Modeling the Radius of Invasion i...IJERD Editor
A thorough review of existing literature indicates that the Buckley-Leverett equation only analyzes
waterflood practices directly without any adjustments on real reservoir scenarios. By doing so, quite a number
of errors are introduced into these analyses. Also, for most waterflood scenarios, a radial investigation is more
appropriate than a simplified linear system. This study investigates the adoption of the Buckley-Leverett
equation to estimate the radius invasion of the displacing fluid during waterflooding. The model is also adopted
for a Microbial flood and a comparative analysis is conducted for both waterflooding and microbial flooding.
Results shown from the analysis doesn’t only records a success in determining the radial distance of the leading
edge of water during the flooding process, but also gives a clearer understanding of the applicability of
microbes to enhance oil production through in-situ production of bio-products like bio surfactans, biogenic
gases, bio acids etc.
Gesture Gaming on the World Wide Web Using an Ordinary Web CameraIJERD Editor
- Gesture gaming is a method by which users having a laptop/pc/x-box play games using natural or
bodily gestures. This paper presents a way of playing free flash games on the internet using an ordinary webcam
with the help of open source technologies. Emphasis in human activity recognition is given on the pose
estimation and the consistency in the pose of the player. These are estimated with the help of an ordinary web
camera having different resolutions from VGA to 20mps. Our work involved giving a 10 second documentary to
the user on how to play a particular game using gestures and what are the various kinds of gestures that can be
performed in front of the system. The initial inputs of the RGB values for the gesture component is obtained by
instructing the user to place his component in a red box in about 10 seconds after the short documentary before
the game is finished. Later the system opens the concerned game on the internet on popular flash game sites like
miniclip, games arcade, GameStop etc and loads the game clicking at various places and brings the state to a
place where the user is to perform only gestures to start playing the game. At any point of time the user can call
off the game by hitting the esc key and the program will release all of the controls and return to the desktop. It
was noted that the results obtained using an ordinary webcam matched that of the Kinect and the users could
relive the gaming experience of the free flash games on the net. Therefore effective in game advertising could
also be achieved thus resulting in a disruptive growth to the advertising firms.
Hardware Analysis of Resonant Frequency Converter Using Isolated Circuits And...IJERD Editor
-LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region[5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
each and every ckt used because it acts as a driver and an isolation to each of the IGBT is provided with one
exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
waveform .The basic goal of this particular analysis is to observe the wave forms and characteristics of
converters with differently positioned passive elements in the form of tank circuits.
Simulated Analysis of Resonant Frequency Converter Using Different Tank Circu...IJERD Editor
LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region [5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
each and every ckt used because it acts as a driver and an isolation to each of the IGBT is provided with one
exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
waveform .The basic goal of this particular analysis is to observe the wave forms and characteristics of
converters with differently positioned passive elements in the form of tank circuits. The supported simulation
is done through PSIM 6.0 software tool
Amateurs Radio operator, also known as HAM communicates with other HAMs through Radio
waves. Wireless communication in which Moon is used as natural satellite is called Moon-bounce or EME
(Earth -Moon-Earth) technique. Long distance communication (DXing) using Very High Frequency (VHF)
operated amateur HAM radio was difficult. Even with the modest setup having good transceiver, power
amplifier and high gain antenna with high directivity, VHF DXing is possible. Generally 2X11 YAGI antenna
along with rotor to set horizontal and vertical angle is used. Moon tracking software gives exact location,
visibility of Moon at both the stations and other vital data to acquire real time position of moon.
“MS-Extractor: An Innovative Approach to Extract Microsatellites on „Y‟ Chrom...IJERD Editor
Simple Sequence Repeats (SSR), also known as Microsatellites, have been extensively used as
molecular markers due to their abundance and high degree of polymorphism. The nucleotide sequences of
polymorphic forms of the same gene should be 99.9% identical. So, Microsatellites extraction from the Gene is
crucial. However, Microsatellites repeat count is compared, if they differ largely, he has some disorder. The Y
chromosome likely contains 50 to 60 genes that provide instructions for making proteins. Because only males
have the Y chromosome, the genes on this chromosome tend to be involved in male sex determination and
development. Several Microsatellite Extractors exist and they fail to extract microsatellites on large data sets of
giga bytes and tera bytes in size. The proposed tool “MS-Extractor: An Innovative Approach to extract
Microsatellites on „Y‟ Chromosome” can extract both Perfect as well as Imperfect Microsatellites from large
data sets of human genome „Y‟. The proposed system uses string matching with sliding window approach to
locate Microsatellites and extracts them.
Importance of Measurements in Smart GridIJERD Editor
- The need to get reliable supply, independence from fossil fuels, and capability to provide clean
energy at a fixed and lower cost, the existing power grid structure is transforming into Smart Grid. The
development of a smart energy distribution grid is a current goal of many nations. A Smart Grid should have
new capabilities such as self-healing, high reliability, energy management, and real-time pricing. This new era
of smart future grid will lead to major changes in existing technologies at generation, transmission and
distribution levels. The incorporation of renewable energy resources and distribution generators in the existing
grid will increase the complexity, optimization problems and instability of the system. This will lead to a
paradigm shift in the instrumentation and control requirements for Smart Grids for high quality, stable and
reliable electricity supply of power. The monitoring of the grid system state and stability relies on the
availability of reliable measurement of data. In this paper the measurement areas that highlight new
measurement challenges, development of the Smart Meters and the critical parameters of electric energy to be
monitored for improving the reliability of power systems has been discussed.
Study of Macro level Properties of SCC using GGBS and Lime stone powderIJERD Editor
The document summarizes a study on the use of ground granulated blast furnace slag (GGBS) and limestone powder to replace cement in self-compacting concrete (SCC). Tests were conducted on SCC mixes with 0-50% replacement of cement with GGBS and 0-20% replacement with limestone powder. The results showed that replacing 30% of cement with GGBS and 15% with limestone powder produced SCC with the highest compressive strength of 46MPa, meeting fresh property requirements. The study concluded that this ternary blend of cement, GGBS and limestone powder can improve SCC properties while reducing costs.
5th LF Energy Power Grid Model Meet-up SlidesDanBrown980551
5th Power Grid Model Meet-up
It is with great pleasure that we extend to you an invitation to the 5th Power Grid Model Meet-up, scheduled for 6th June 2024. This event will adopt a hybrid format, allowing participants to join us either through an online Mircosoft Teams session or in person at TU/e located at Den Dolech 2, Eindhoven, Netherlands. The meet-up will be hosted by Eindhoven University of Technology (TU/e), a research university specializing in engineering science & technology.
Power Grid Model
The global energy transition is placing new and unprecedented demands on Distribution System Operators (DSOs). Alongside upgrades to grid capacity, processes such as digitization, capacity optimization, and congestion management are becoming vital for delivering reliable services.
Power Grid Model is an open source project from Linux Foundation Energy and provides a calculation engine that is increasingly essential for DSOs. It offers a standards-based foundation enabling real-time power systems analysis, simulations of electrical power grids, and sophisticated what-if analysis. In addition, it enables in-depth studies and analysis of the electrical power grid’s behavior and performance. This comprehensive model incorporates essential factors such as power generation capacity, electrical losses, voltage levels, power flows, and system stability.
Power Grid Model is currently being applied in a wide variety of use cases, including grid planning, expansion, reliability, and congestion studies. It can also help in analyzing the impact of renewable energy integration, assessing the effects of disturbances or faults, and developing strategies for grid control and optimization.
What to expect
For the upcoming meetup we are organizing, we have an exciting lineup of activities planned:
-Insightful presentations covering two practical applications of the Power Grid Model.
-An update on the latest advancements in Power Grid -Model technology during the first and second quarters of 2024.
-An interactive brainstorming session to discuss and propose new feature requests.
-An opportunity to connect with fellow Power Grid Model enthusiasts and users.
Salesforce Integration for Bonterra Impact Management (fka Social Solutions A...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on integration of Salesforce with Bonterra Impact Management.
Interested in deploying an integration with Salesforce for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
Dive into the realm of operating systems (OS) with Pravash Chandra Das, a seasoned Digital Forensic Analyst, as your guide. 🚀 This comprehensive presentation illuminates the core concepts, types, and evolution of OS, essential for understanding modern computing landscapes.
Beginning with the foundational definition, Das clarifies the pivotal role of OS as system software orchestrating hardware resources, software applications, and user interactions. Through succinct descriptions, he delineates the diverse types of OS, from single-user, single-task environments like early MS-DOS iterations, to multi-user, multi-tasking systems exemplified by modern Linux distributions.
Crucial components like the kernel and shell are dissected, highlighting their indispensable functions in resource management and user interface interaction. Das elucidates how the kernel acts as the central nervous system, orchestrating process scheduling, memory allocation, and device management. Meanwhile, the shell serves as the gateway for user commands, bridging the gap between human input and machine execution. 💻
The narrative then shifts to a captivating exploration of prominent desktop OSs, Windows, macOS, and Linux. Windows, with its globally ubiquitous presence and user-friendly interface, emerges as a cornerstone in personal computing history. macOS, lauded for its sleek design and seamless integration with Apple's ecosystem, stands as a beacon of stability and creativity. Linux, an open-source marvel, offers unparalleled flexibility and security, revolutionizing the computing landscape. 🖥️
Moving to the realm of mobile devices, Das unravels the dominance of Android and iOS. Android's open-source ethos fosters a vibrant ecosystem of customization and innovation, while iOS boasts a seamless user experience and robust security infrastructure. Meanwhile, discontinued platforms like Symbian and Palm OS evoke nostalgia for their pioneering roles in the smartphone revolution.
The journey concludes with a reflection on the ever-evolving landscape of OS, underscored by the emergence of real-time operating systems (RTOS) and the persistent quest for innovation and efficiency. As technology continues to shape our world, understanding the foundations and evolution of operating systems remains paramount. Join Pravash Chandra Das on this illuminating journey through the heart of computing. 🌟
Letter and Document Automation for Bonterra Impact Management (fka Social Sol...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on automated letter generation for Bonterra Impact Management using Google Workspace or Microsoft 365.
Interested in deploying letter generation automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slackshyamraj55
Discover the seamless integration of RPA (Robotic Process Automation), COMPOSER, and APM with AWS IDP enhanced with Slack notifications. Explore how these technologies converge to streamline workflows, optimize performance, and ensure secure access, all while leveraging the power of AWS IDP and real-time communication via Slack notifications.
Digital Marketing Trends in 2024 | Guide for Staying AheadWask
https://www.wask.co/ebooks/digital-marketing-trends-in-2024
Feeling lost in the digital marketing whirlwind of 2024? Technology is changing, consumer habits are evolving, and staying ahead of the curve feels like a never-ending pursuit. This e-book is your compass. Dive into actionable insights to handle the complexities of modern marketing. From hyper-personalization to the power of user-generated content, learn how to build long-term relationships with your audience and unlock the secrets to success in the ever-shifting digital landscape.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
We will explore the capabilities of AI in understanding XML markup languages and autonomously creating structured XML content. Additionally, we will examine the capacity of AI to enrich plain text with appropriate XML markup. Practical examples and methodological guidelines will be provided to elucidate how AI can be effectively prompted to interpret and generate accurate XML markup.
Further emphasis will be placed on the role of AI in developing XSLT, or schemas such as XSD and Schematron. We will address the techniques and strategies adopted to create prompts for generating code, explaining code, or refactoring the code, and the results achieved.
The discussion will extend to how AI can be used to transform XML content. In particular, the focus will be on the use of AI XPath extension functions in XSLT, Schematron, Schematron Quick Fixes, or for XML content refactoring.
The presentation aims to deliver a comprehensive overview of AI usage in XML development, providing attendees with the necessary knowledge to make informed decisions. Whether you’re at the early stages of adopting AI or considering integrating it in advanced XML development, this presentation will cover all levels of expertise.
By highlighting the potential advantages and challenges of integrating AI with XML development tools and languages, the presentation seeks to inspire thoughtful conversation around the future of XML development. We’ll not only delve into the technical aspects of AI-powered XML development but also discuss practical implications and possible future directions.
Your One-Stop Shop for Python Success: Top 10 US Python Development Providersakankshawande
Simplify your search for a reliable Python development partner! This list presents the top 10 trusted US providers offering comprehensive Python development services, ensuring your project's success from conception to completion.
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
An English 🇬🇧 translation of a presentation to the speech I gave about the main changes brought by CCS TSI 2023 at the biggest Czech conference on Communications and signalling systems on Railways, which was held in Clarion Hotel Olomouc from 7th to 9th November 2023 (konferenceszt.cz). Attended by around 500 participants and 200 on-line followers.
The original Czech 🇨🇿 version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
Programming Foundation Models with DSPy - Meetup SlidesZilliz
Prompting language models is hard, while programming language models is easy. In this talk, I will discuss the state-of-the-art framework DSPy for programming foundation models with its powerful optimizers and runtime constraint system.
International Journal of Engineering Research and Development (IJERD)
1. International Journal of Engineering Research and Development
e-ISSN: 2278-067X, p-ISSN: 2278-800X, www.ijerd.com
Volume 8, Issue 8 (September 2013), PP. 26-32
www.ijerd.com 26 | Page
Design and Implementation of High Speed Low Power
Viterbi Decoder
BaburaoKodavati1
, Subhrajeeth Pradhan2
, G.Naveen Kumar3
, Srikanth patnaiak4
1, 3, 4
Asst.Prof,Giet,Gunupur,Rayagada,Odisha-765022.
2
Hod Of Ece Department,Giet, Gunupur, Rayagada, Odisha-765022.
Abstract:- Convolution encoding with Viterbi decoding is a powerful method for error checking. It has been
widely deployed in many wireless communication systems to improve the limited capacity of the
communication channels. The Viterbi algorithm, which is the most extensively employed decoding algorithm
for convolution codes. In this paper, we present an implementation of Viterbi Decoder for code rate of ½ and for
constraint length of 9 which is employed in present technologies. The Viterbi algorithm is commonly used in a
wide range of communications and data storage applications.Thispaper discusses about architecture for a Viterbi
Decoder using VLSI design techniques at circuit level. The Viterbi decoder comprises of BMU, PMU and a
SMU. Communication within the decoder blocks is controlled by the Request-Acknowledge handshake pair
which signals that data is ready for process. The design of various units of Viterbi Decoder is done by
VERILOG HDL language. The simulation results show the decoder output of the encoded bits which are
nothing but the bits which we are applied to conventional encoder.
I. INTRODUCTION
Convolution coding has been used in communication systems including deep space
communications and wireless communications. It offers an alternative to block codes for transmission over a
noisy channel. An advantage of convolution coding is that it can be applied to a continuous data stream as well
as to blocks of data. IS-95, a wireless digital cellular standard for CDMA (code division multiple access),
employs convolution coding. A third generation wireless cellular standard, under preparation, plans to
adopt turbo coding, which stems from convolution coding. The Viterbi decoding algorithm, proposed in 1967
by Viterbi, is a decoding process for convolution codes in memory-less noise [52]. The algorithm can be
applied to a host of problems encountered in the design of communication systems [52]. The Viterbi
decoding algorithm provides both a maximum-likelihood and a maximum a posterior algorithm. A
maximum a posterior algorithm identifies a code word that maximizes the conditional probability of the
decoded code word against the received code word, in contrast a maximum likelihood algorithm identifies a
code word that maximizes the conditional probability of the received code word against the decoded code
word. The two algorithms give the same results when the source information has a uniform distribution.
Traditionally, performance and silicon area are the two most important concerns in VLSI design.
Recently, power dissipation has also become an important concern, especially in battery- powered applications,
such as cellular phones, pagers and laptop computers. Power dissipation can be classified into two categories,
static power dissipation and dynamic power dissipation Typically, static power dissipation is due to
various leakage currents, while dynamic power dissipation is a result of charging and discharging the
parasitic capacitance of transistors andwires. Since the dynamic power dissipation accounts for about 80 to 90
percent of overall power dissipation in CMOS circuits; numerous techniques have been proposed to
reduce dynamic power dissipation. These techniques can be applied at different levels of digital design, such as
the algorithmic level, the architectural level, the gate level and, the circuit level.
A viterbi decoder uses the Viterbi algorithm for decoding a bit stream that has been encoded using
Forward error correction based on a Convolution code. The Viterbi algorithm is commonly used in a wide range
of communications and data storage applications. It is used for decoding convolution codes, in baseband
detection for wireless systems, and also for detection of recorded data in magnetic disk drives. The requirements
for the Viterbi decoder or Viterbi detector, which is a processor that implements the Viterbi algorithm, depend
on the applications where they are used. This results in very wide range of required data throughputs and power
or area requirements.
Viterbi detectors are used in cellular telephones with low data rates, of the order below 1Mb/s but with
very low energy dissipation requirement. They are used for trellis code demodulation in telephone line modems,
where the throughput is in the range of tens of kb/s, with restrictive limits in power dissipation and the area/cost
of the chip. On the opposite end, very high speed Viterbi detectors are used in magnetic disk drive read
channels, with throughputs over 600Mb/s. But at these high speeds, area and power are still limited.
2. Design and Implementation of High Speed Low Power Viterbi Decoder
www.ijerd.com 27 | Page
Convolutional coding has been used in communication systems including deep space communications
and wireless communications. It offers an alternative to block codes for transmission over a noisy channel. An
advantage of convolutional coding is that it can be applied to a continuous data stream as well as to blocks of
data. IS-95, a wireless digital cellular standard for CDMA (code division multiple access), employs
convolutional coding.
II. ARCHITECTURE OF VITERBI DECODER
FIG-2.1 Architecture of the VITERBI DECODER
In the viterbi decoding approach the trace-back (TB) and the register-exchange (RE) methods are the
two major techniques used for the path history management in the chip designs of Viterbi decoders. The TB
method takes up less area but requires much more time as compared to RE method because it needs to search or
trace the survivor path back sequentially. But the major disadvantage of the RE approach is that its routing cost
is very high especially in the case of long-constraint lengths and it requires much more resources.
2.2 Branch Metric Computation (BMC)
For each state, the Hamming distance between the received bits and the expected bits is calculated.
Hamming distance between two symbols of the same length is calculated as the number of bits that are different
between them. These branch metric values are passed to Block 2. If soft decision inputs were to be used, branch
metric would be calculated as the squared Euclidean distance between the received symbols [21]. The squared
Euclidean distance is given as (a1-b1)2
+ (a2-b2)2
+ (a3-b3)2
where a1, a2, a3 and b1, b2, b3 are the three soft
decision bits of the received and expected bits respectively.
value Meaning
000 strongest 0
001 relatively strong 0
010 relatively weak 0
011 weakest 0
100 weakest 1
101 relatively weak 1
110 relatively strong 1
111 strongest 1
FIG-2.2 A sample implementation of a branch metric unit
2.3 Path Metric Computation and Add-Compare-Select (ACS) Unit
The path metric or error probability for each transition state at a particular time instant is measured as
the sum of the path metric for its preceding state and the branch metric between the previous state and the
present state. The initial path metric at the first time instant is infinity for all states except state 0. For each state,
there are two possible predecessors. The mechanism of calculating the predecessors (and successors) The path
3. Design and Implementation of High Speed Low Power Viterbi Decoder
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metrics from both these predecessors are compared and the one with the smallest path metric is selected. This is
the most probable transition that occurred in the original message. In addition, a single bit is also stored for each
state which specifies whether the lower or upper predecessor was selected.
Fig-2.3 A sample implementation of the path metric unit
In cases where both paths result in the same path metric to the state, either the higher or lower state
may consistently be chosen as the surviving predecessor. For the purpose of this paper the higher state is
consistently chosen as the surviving predecessor. Finally, the state with the least accumulated path metric at the
current time instant is located. This state is called the global winner and is the state from which traceback
operation will begin. This method of starting the trace back operation from the global winner instead of an
arbitrary state was described by Linda Bracken bury [22] in her design of an asynchronous Viterbi decoder. This
greatly improves probability of finding the correct traceback path quicker and hence reduces the amount of
history information that needs to be maintained. It also reduces the number of updates required to the surviving
path. Both these measures result in improved energy savings. The values for the surviving predecessors (also
called local winners) and the global winner are passed to Block 3.
Fig -2.4 A sample implementation of an ACS unit
2.4 Traceback Unit
The global winner for the current state is received from Block 2. Its predecessor is selected in the
manner . In this way, working backwards through the trellis, the path with the minimum accumulated path
metric is selected. This path is known as the traceback path. A diagrammatic description will help visualize this
process.the trellis diagram for a ½ K=3 (7, 5) coder with sample input taken as the received data.
Fig -2.5 Selected minimum error path for a1/2 k=3(7,5) decoder
4. Design and Implementation of High Speed Low Power Viterbi Decoder
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The state having minimum accumulated error at the last time instant is State 10 and traceback is
started here. Moving backwards through the trellis, the minimum error path out of the two possible predecessors
from that state is selected. This path is marked in blue. The actual received data is described at the bottom while
the expected data written in blue along the selected path. It is observed that at time slot three there was an error
in received data (11). This was corrected to (10) by the decoder.
Fig-2.6 Schematic representation of the viterbi decoder
Local winner information must be stored for five times the constraint length. For a K =7 decoder, this
results in storing history for 7 x 5 = 35 time slots. The state of the decoder at the time instant 35 time slots prior
can then be accurately determined. This state value is passed to Block 4. At the next time slot, all the trellis
values are shifted left to the previous time slot. The path metric for the last received data and compute the
minimum error path is then calculated. If the global winner at this stage is not a child of the previous global
winner, the traceback path has to be updated accordingly until the traceback state is a child of the previous state.
Fig-2.7 Block diagram of the Trace Back unit
Multiple traceback paths are possible and it may be thought that traceback up to the first bit is
necessary to correctly determine the surviving path. However, it was found that all possible paths converge
within a certain distance or depth of trace back. This information is useful as it allows the setting of a certain
trace back depth beyond which it is neither necessary nor advantageous to store path metric and other
information. This greatly reduces memory storage requirements and hence energy consumption of the decoder.
Empirical observations showed that a depth of five times the constraint length was sufficient to ensure merging
of paths . Therefore, local winner information is stored for 35 slots (five times seven) in the decoder used for
this paper. Block 4. Data Input Determination Now going forwards through the traceback path, the state
transitions at successive time intervals are studies and the data bit that would have caused this transition is
determined. This represents the decoded output.
Determining Successors to a particular State Each state is represented by 6 shift registers (in the case of
a K=7 encoder or decoder). The next state can therefore be obtained by a right shift of the values of the shift
registers. The first shift register is given a value of 0. The resulting state represents the next state of the coder if
the input bit was 0. By adding 32 (1x25) to this value, the next state of the coder if the input bit was 1
Determining Predecessors to a particular State In a similar way, the first predecessor can be calculated this time
by a left shift of the values of the shift registers. By adding one (1x20) to this value, the value of the second
predecessor to the state is derived.
2.5 State Metric Storage: The block stores the partial path metric of each state at the current stage.
5. Design and Implementation of High Speed Low Power Viterbi Decoder
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2.6 Output Generator:
This block generates the decoded output sequence. In the traceback approach, the block incorporates
combinational logic, which traces back along the survivor path and latches the path (equivalently the decoded
output sequence) to a register.
2.7 Encoding Mechanism
Data is coded by using a convolutional encoder. It consists of a series of shift registers and an
associated combinatorial logic. The combinatorial logic is usually a series of exclusive-or gates. The
conventional encoder ½ K=7, (171,133) is used for the purpose of this paper. The octal numbers 171 and 133
when represented in binary form correspond to the connection of the shift registers to the upper and lower
exclusive-or gates respectively. Figure 3.1 represents this convolutional encoder that will be used for the paper.
2.8 Decoding Mechanism
There are two main mechanisms by which Viterbi decoding may be carried out namely, the Register
Exchange mechanism and the Traceback mechanism. Register exchange mechanisms, as explained by Ranpara
and Sam Ha store the partially decoded output sequence along the path. The advantage of this approach is that it
eliminates the need for traceback and hence reduces latency. However at each stage, the contents of each
register needs to be copied to the next stage.
This makes the hardware complex and more energy consuming than the traceback mechanism. Traceback
mechanisms use a single bit to indicate whether the survivor branch came from the upper or lower path. This
information is used to traceback the surviving path from the final state to the initial state. This path can then be
used to obtain the decoded sequence. Traceback mechanisms prove to be less energy consuming and will hence
be the approach followed in this paper.
Decoding may be done using either hard decision inputs or soft decision inputs. Inputs that arrive at the
receiver may not be exactly zero or one. Having been affected by noise, they will have values in between and
even higher or lower than zero and one. The values may also be complex in nature.
In the hard decision Viterbi decoder, each input that arrives at the receiver is converted into a binary
value (either 0 or 1). In the soft decision Viterbi decoder, several levels are created and the arriving input is
categorized into a level that is closest to its value. If the possible values are split into 8 decision levels, these
levels may be represented by 3 bits and this is known as a 3 bit Soft decision.
This paper uses a hard decision Viterbi decoder for the purpose of developing and verifying the new
energy saving algorithm. Once the algorithm is verified, a soft decision Viterbi decoder may be used in place of
the hard decision decoder. Figure 3.2 shows the various stages required to decode data using the Viterbi
Algorithm. The decoding mechanism comprises of three major stages namely the Branch Metric Computation
Unit, the Path Metric Computation and Add-Compare-Select (ACS) Unit and the Traceback Unit.
3.Main Objectives: The main objectives of this paper are as follows
1. An understanding of the background literature relevant to error detection and error control mechanisms
as currently used in packetized digital communication networks.
2. A detailed understanding of the concept of convolutional coding, and decoding using the Viterbi
algorithm.
3. An implementation of the Viterbi algorithm in verilog so it is working correctly by comparing its
performance with that of the Viterbi decoder function provided by verilog (A designed Viterbi decoder is
needed because verilog does not provide access to the code.
4. A resolution of questions that still need to be answered about the T- algorithm including the correct
initialization of component decoders and the stability of the feedback mechanism
5. An implementation in verilog of the T- algorithm as a modification of the Viterbi algorithm.
6. An evaluation of the T- algorithm in terms of its accuracy and capacity for achieving energy saving
Timing Analysis will be performed on the basis of bit-error performance, packet loss rates and execution time
(considered to provide a first order approximation to energy consumption).
III. RESULTS
Fig-4.1 Top Module of VITERBI DECODER
6. Design and Implementation of High Speed Low Power Viterbi Decoder
www.ijerd.com 31 | Page
In viterbi decoder it has 4 modules BMU,PMU,ACSU,SMU where the input is taken by the BMU and
output arrives at SMU
Fig-4.2Control Unit SCHEMATIC DIAGRAM
Fig-4.3 TRACEBACK UNIT BLOCK DIAGRAM
In trace back unit the input will be taken from the add compare select unit and again it will trace back
to the path metric whether it is the shortest path are not it calculate and it will send to the survivor metric unit
Fig-4.4 TRACEBACK UNIT WAVEFORM
Reset-input;Clock1-input;Clock2-input;Lnit-input;Hold-input;Data_TB-output
IV. CONCLUSION
We have proposed a high speed low power VD design for TCM systems.theprecomputation
architecture that incorporates T-algorithm efficiently reduces the power consumption of VDs without reducing
the decoding speed appreciably. we have also analysed precomputation algorithm .where the optimal
precomputation steps are calculated and dicussed.this algorithm is suitable for TCMsystems which always
employ high rate convolutional code.finally we presented a design case.Both the ACSU and SMU are modified
to correctly to decode the signal FPGA and power estimation results show that ,compared with the full trellis
VD without a low power scheme,theprecomputation VD could reduce the power consumption by 70% with only
11% reduction of the maximum decoding speed.
By using FPGA device and hybrid microprocessor the decoding benefits can be achieved in future. In
future to improve the decoder performance the Viterbi algorithm is carried out in reconfigurable
hardware. power saving architecture can be designed for the above decoder which is executable in the mobile
devices. Viterbi decoder can also be implemented using verilog. Therefore in the future Viterbi algorithm may
be used for various scenarios. So in the future the complexity can be greatly reduced. By using FPGA device
7. Design and Implementation of High Speed Low Power Viterbi Decoder
www.ijerd.com 32 | Page
and hybrid microprocessor the decoding benefits can be achieved in future. In future to improve the decoder
performance the Viterbi algorithm is carried out in reconfigurable hardware. power saving architecture can be
designed for the above decoder which is executable in the mobile devices. Viterbi decoder can also be
implemented using verilog. Therefore in the future Viterbi algorithm may be used for various scenarios. So in
the future the complexity can be greatly reduced.
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