Recently, indoor Optical Wireless (OW) connectivity has gained significant attention as a possible
alternative to tackle the problem of bottleneck access and as an improvement to ever more conventional RF
/ microwave connections. In indoor OW communication, OOK encoding is more widely used owing to its
effective usage of bandwidth and robustness to timing errors, given the fact that the power consumption is
less than PPM. The modulation format in this research work is Q-array PPM over lasers, with modulation
of power. The effects of the analysis are analyzed numerically in view of the amount of bit error (BER). It is
shown that, because of coding for 4PPM framework, the bit error performance is increased. For instance,
an LDPC-coded device with stable foundation radiation provides a important coding improvement of 5 to 6
dB over uncoded device at BER in the order of 10-8 and 10-12 respectively.
Performance Evaluation of DCF Length for High Scalability NG-PON2TELKOMNIKA JOURNAL
Next Generation Passive Optical Network Stage 2 (NG-PON2) have to resolve the problem like demand each user, for example, HDTV, 3DTV, Hologram and Telemedicine. The research designed Passive Optical Network (PON), which is meet requirements of NG-PON2. Using stacked 4 Optical Line Terminal (OLT) with an aggregate 40 Gbps transmitted on fiber Single Mode Fiber (SMF) and Dispersion Compensation Fiber (DCF) by comparing the system without DCF cable. On the condition of minimum standards, the range of 40 km with a power splitter 1:64 only 9:01% power difference while the increased in the Q factor of 65.5%. With these results, it can be said that systems using DCF can be used optimally. In addition, with the power splitter 1: 4 and a lower power worth 0 dBm can produce a range of 150% further. With the same distance as far as 40 km, this research increasing power splitter 6 times increase compared with previous research.
Hardware Architecture of Complex K-best MIMO DecoderCSCJournals
This paper presents a hardware architecture of complex K-best Multiple Input Multiple Output (MIMO) decoder reducing the complexity of Maximum Likelihood (ML) detector. We develop a novel low-power VLSI design of complex K-best decoder for MIMO and 64 QAM modulation scheme. Use of Schnorr-Euchner (SE) enumeration and a new parameter, Rlimit in the design reduce the complexity of calculating K-best nodes to a certain level with increased performance. The total word length of only 16 bits has been adopted for the hardware design limiting the bit error rate (BER) degradation to 0.3 dB with list size, K and Rlimit equal to 4. The proposed VLSI architecture is modeled in Verilog HDL using Xilinx and synthesized using Synopsys Design Vision in 45 nm CMOS technology. According to the synthesize result, it achieves 1090.8 Mbps throughput with power consumption of 782 mW and latency of 0.33 us. The maximum frequency the design proposed is 181.8 MHz.
A perceptible innovation in the indoor remote correspondence systems which supports the wireless communication networks is visible light communication (VLC). It is an add-on with the emerging green communication technology. VLC uses light discharging diodes (LEDs) for the purposes of brightening and communication. To accomplish monetary and vitality proficient correspondences, non-orthogonal multiple access (NOMA) improves the framework throughput by upgrading the efficacies of the spectrum. In indoor VLC systems, the increase in the gain ratio power allocation (GRPA) of NOMA dispenses more noteworthy sign capacity to clients of poor channels to accomplish unbiased access with high information rate. Nevertheless, the current GRPA techniques created for radio recurrence channels are not really efficient in all VLC channel and radiance cases. This investigation tries to substantiate the sentenced contributions. Initially, a GRPA strategy based on VLC channels which alters the counting of power and proportions of channel that upgrade the throughput of NOMA-VLC has been proposed. Secondly, owing to the downsides of straightforwardly dissecting the throughput of NOMA-VLC, an elective lower bound based on a VLC channel model to accomplish the comparisons of throughput has been proposed. It is demonstrated that the proposed elective lower bound is asymptotic and relatively compact in terms of the throughput of NOMA-VLC. Finally, for the instance of LED heights that are more prominent than 1 meter, a local optimum solution utilizing the proposed technique is logically proven to be dependent on the elective bound of the throughput obtained from VLC network.
Performance Evaluation of DCF Length for High Scalability NG-PON2TELKOMNIKA JOURNAL
Next Generation Passive Optical Network Stage 2 (NG-PON2) have to resolve the problem like demand each user, for example, HDTV, 3DTV, Hologram and Telemedicine. The research designed Passive Optical Network (PON), which is meet requirements of NG-PON2. Using stacked 4 Optical Line Terminal (OLT) with an aggregate 40 Gbps transmitted on fiber Single Mode Fiber (SMF) and Dispersion Compensation Fiber (DCF) by comparing the system without DCF cable. On the condition of minimum standards, the range of 40 km with a power splitter 1:64 only 9:01% power difference while the increased in the Q factor of 65.5%. With these results, it can be said that systems using DCF can be used optimally. In addition, with the power splitter 1: 4 and a lower power worth 0 dBm can produce a range of 150% further. With the same distance as far as 40 km, this research increasing power splitter 6 times increase compared with previous research.
Hardware Architecture of Complex K-best MIMO DecoderCSCJournals
This paper presents a hardware architecture of complex K-best Multiple Input Multiple Output (MIMO) decoder reducing the complexity of Maximum Likelihood (ML) detector. We develop a novel low-power VLSI design of complex K-best decoder for MIMO and 64 QAM modulation scheme. Use of Schnorr-Euchner (SE) enumeration and a new parameter, Rlimit in the design reduce the complexity of calculating K-best nodes to a certain level with increased performance. The total word length of only 16 bits has been adopted for the hardware design limiting the bit error rate (BER) degradation to 0.3 dB with list size, K and Rlimit equal to 4. The proposed VLSI architecture is modeled in Verilog HDL using Xilinx and synthesized using Synopsys Design Vision in 45 nm CMOS technology. According to the synthesize result, it achieves 1090.8 Mbps throughput with power consumption of 782 mW and latency of 0.33 us. The maximum frequency the design proposed is 181.8 MHz.
A perceptible innovation in the indoor remote correspondence systems which supports the wireless communication networks is visible light communication (VLC). It is an add-on with the emerging green communication technology. VLC uses light discharging diodes (LEDs) for the purposes of brightening and communication. To accomplish monetary and vitality proficient correspondences, non-orthogonal multiple access (NOMA) improves the framework throughput by upgrading the efficacies of the spectrum. In indoor VLC systems, the increase in the gain ratio power allocation (GRPA) of NOMA dispenses more noteworthy sign capacity to clients of poor channels to accomplish unbiased access with high information rate. Nevertheless, the current GRPA techniques created for radio recurrence channels are not really efficient in all VLC channel and radiance cases. This investigation tries to substantiate the sentenced contributions. Initially, a GRPA strategy based on VLC channels which alters the counting of power and proportions of channel that upgrade the throughput of NOMA-VLC has been proposed. Secondly, owing to the downsides of straightforwardly dissecting the throughput of NOMA-VLC, an elective lower bound based on a VLC channel model to accomplish the comparisons of throughput has been proposed. It is demonstrated that the proposed elective lower bound is asymptotic and relatively compact in terms of the throughput of NOMA-VLC. Finally, for the instance of LED heights that are more prominent than 1 meter, a local optimum solution utilizing the proposed technique is logically proven to be dependent on the elective bound of the throughput obtained from VLC network.
Performance evaluation of VLC system using new modulation approachjournalBEEI
We propose a modified OFDM modulation based on multiband scheme for visible light communications (VLC) system. The method called catenated-OFDM VLC system can efficiently boost the propagation distance and combat multipath induced the inter symbol interference and inter carrier interference. Design parameters such as number of optical bands, input power, distance and data rate are varied to see their effect on the system performances. Simulation analysis is done using Optisys software Ver. 11.0. The results show that the proposed system offers a good performance at longer transmission distance of 12 m for input power of 2 dBm in case of Band=3 with 10 Gbps data rate. BER curves also indicates that the proposed system can be operated at very high data rate of 15 Gbps. This exhibits the ability of the proposed system to be one of the candidate for future optical wireless communication system.
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.
A NEW HYBRID DIVERSITY COMBINING SCHEME FOR MOBILE RADIO COMMUNICATION SYSTEM...ijcsit
Diversity combining is a technique in wireless network that uses multiple antenna system to improve the quality of radio signal. Mobile radio system suffers multipath propagation due to signal obstruction in the channel. A new hybridized diversity combining scheme consisting of Equal Gain Combining (EGC) and Maximal Ratio Combining (MRC) was proposed in this paper. Theperformance of the hybrid model was evaluated using Outage Probability (Pout) and Processing time (Pt) at different Signal-to-Noise Ratio (SNR) and Signal Paths (L=2,3) for 4-QAM and 8-QAM Modulation Schemes. A mathematical expression for the hybrid EGC-MRC was realized using the Probability Density Function (PDF) of the Nakagami fading channel. MATLAB R2015b software was used for the model simulation. The result shows that hybrid EGC-MRC outperforms the standalone EGC and MRC schemes by having lower Pout and Pt values. Hence, hybrid EGC-MRC exhibits enhanced potentials to mitigate multipath propagation at reduced
system complexity.
Diversity combining is a technique in wireless network that uses multiple antenna system to improve the quality of radio signal. Mobile radio system suffers multipath propagation due to signal obstruction in the channel. A new hybridized diversity combining scheme consisting of Equal Gain Combining (EGC) and Maximal Ratio Combining (MRC) was proposed in this paper. Theperformance of the hybrid model was evaluated using Outage Probability (Pout) and Processing time (Pt) at different Signal-to-Noise Ratio (SNR) and Signal Paths (L=2,3) for 4-QAM and 8-QAM Modulation Schemes. A mathematical expression for the hybrid EGC-MRC was realized using the Probability Density Function (PDF) of the Nakagami fading channel. MATLAB R2015b software was used for the model simulation. The result shows that hybrid EGC-MRC outperforms the standalone EGC and MRC schemes by having lower Pout and Pt values. Hence, hybrid EGC-MRC exhibits enhanced potentials to mitigate multipath propagation at reduced system complexity.
Performance evaluation of different spectrum sensing techniques for realistic...ijwmn
In this paper, the performance assessment of five different detection techniques from spectrum sensing
perspective in cognitive radio networks is proposed and implemented using the realistic implementation
oriented model (R-model) with signal processing operations. The performance assessment of the different
sensing techniques in the existence of unknown or imprecisely known impulsive noise levels is done by
considering the signal detection in cognitive radio networks under a non-parametric multisensory detection
scenario. The examination focuses on performance comparison of basic spectrum sensing mechanisms as,
energy detection (ED) and cyclostationary feature detection (CSFD) along with the eigenvalue-based
detection methods namely, Maximum-minimum eigenvalue detection (MMED), Roy’s largest Root Test
(RLRT) which requires knowledge of the noise variance and Generalized Likelihood Ratio Test (GLRT)
which can be implemented as a test of the largest eigenvalues vs. Maximum-likelihood estimates a noise
variance. From simulation results it is observed that the detection performance of the GLRT method is
better than the other techniques in realistic implementation oriented model.
Negative image amplifier technique for performance enhancement of ultra wideb...IJECEIAES
The paper aims at designing of two stage cascaded ultra-wideband (UWB) low noise amplifier (LNA) by using negative image amplifier technique. The objective of this article is to show the performance improvement using negative image amplifier technique and realization of negative valued lumped elements into microstrip line geometry. The innovative technique to realize the negative lumped elements are carried out by using Richard’s Transformation and transmission line calculation. The AWR microwave office tool is used to obtain characteristics of UWB LNA design with hybrid microwave integrated circuit (HMIC) technology. The 2-stage cascaded LNA design using negative image amplifier technique achieves average gain of 23dB gain and low noise figure of less than 2dB with return loss less than -8dB for UWB 3-10GHz. The Proper bias circuit is extracted using DC characteristics of transistor at biasing point 2V, 20mA and discussed in detail with LNA layout. The negative image matching technique is applied for both input and output matching network. This work will be useful for all low power UWB wireless receiver applications.
Performance analysis and monitoring of various advanced digital modulation an...IJCNCJournal
To achieve better calculative performance in optical fiber communication and for simplicity of
implementation different digital modulation, detection and multiplexing techniques are used. These
techniques maximize the spectral efficiency. This paper reviews a tabular comparative analysis with 3D
graphical representation for different optical digital modulation formats and multiplexing techniques
within and beyond 400 Gb/s. In this particular article we survey about different parameters related to
digital fiber optic communication.
Powerful business model for fixed wireless data using outdoor antennas - PaperAndre Fourie
Paper presented at the 2nd Africa Radio Comms Conference in Johannesburg - Nov 2015
By Andre Fourie
The revenue that can be generated by an LTE base station is influenced by the quality of the signal received by the customer premise equipment (CPE). Most CPE come with omni-directional indoor antennas, but have provision for the connection to external antennas.
Substituting the indoor antennas for directional outdoor antennas has a marked effect on the data transfer speeds of the network. There are two reasons for this. Firstly, outdoor antennas are physically larger than their indoor counterparts and thus have a higher gain. The increase in antenna gain translates directly to an increase in received signal strength. The second advantage is that the outdoor antenna sits in an environment that has much better propagating properties than the indoor antenna. Tests have shown that data speeds 3-5 times faster are possible using external antennas compared to indoor antennas.
It is shown, using a primitive financial model that fairly large financial gains can be made by equipping CPE devices with external antennas.
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.
Implementation Cost Analysis of the Interpolator for the Wimax Technologyiosrjce
The design of the multirate filter (programmable) has been proposed which can be used in digital
transceivers that meets 802.16d/e (wimax) standard in the wireless communication system. Wimax is a
technology emerging in the wireless communication system in order to increase the broadband wireless internet
access. As there is wide spread need of the digital representation of the signal for the transmission and storage
which create the challenges in DSP [1]. In this paper, analysis of the implementation cost of interpolator for the
wimax technology, and cost of interpolator is analyzed on the basis of number of adders and multiplier. The
Filters are designed using the FDA (filters design and analysis) tool in MATLAB.
Performance evaluation of VLC system using new modulation approachjournalBEEI
We propose a modified OFDM modulation based on multiband scheme for visible light communications (VLC) system. The method called catenated-OFDM VLC system can efficiently boost the propagation distance and combat multipath induced the inter symbol interference and inter carrier interference. Design parameters such as number of optical bands, input power, distance and data rate are varied to see their effect on the system performances. Simulation analysis is done using Optisys software Ver. 11.0. The results show that the proposed system offers a good performance at longer transmission distance of 12 m for input power of 2 dBm in case of Band=3 with 10 Gbps data rate. BER curves also indicates that the proposed system can be operated at very high data rate of 15 Gbps. This exhibits the ability of the proposed system to be one of the candidate for future optical wireless communication system.
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.
A NEW HYBRID DIVERSITY COMBINING SCHEME FOR MOBILE RADIO COMMUNICATION SYSTEM...ijcsit
Diversity combining is a technique in wireless network that uses multiple antenna system to improve the quality of radio signal. Mobile radio system suffers multipath propagation due to signal obstruction in the channel. A new hybridized diversity combining scheme consisting of Equal Gain Combining (EGC) and Maximal Ratio Combining (MRC) was proposed in this paper. Theperformance of the hybrid model was evaluated using Outage Probability (Pout) and Processing time (Pt) at different Signal-to-Noise Ratio (SNR) and Signal Paths (L=2,3) for 4-QAM and 8-QAM Modulation Schemes. A mathematical expression for the hybrid EGC-MRC was realized using the Probability Density Function (PDF) of the Nakagami fading channel. MATLAB R2015b software was used for the model simulation. The result shows that hybrid EGC-MRC outperforms the standalone EGC and MRC schemes by having lower Pout and Pt values. Hence, hybrid EGC-MRC exhibits enhanced potentials to mitigate multipath propagation at reduced
system complexity.
Diversity combining is a technique in wireless network that uses multiple antenna system to improve the quality of radio signal. Mobile radio system suffers multipath propagation due to signal obstruction in the channel. A new hybridized diversity combining scheme consisting of Equal Gain Combining (EGC) and Maximal Ratio Combining (MRC) was proposed in this paper. Theperformance of the hybrid model was evaluated using Outage Probability (Pout) and Processing time (Pt) at different Signal-to-Noise Ratio (SNR) and Signal Paths (L=2,3) for 4-QAM and 8-QAM Modulation Schemes. A mathematical expression for the hybrid EGC-MRC was realized using the Probability Density Function (PDF) of the Nakagami fading channel. MATLAB R2015b software was used for the model simulation. The result shows that hybrid EGC-MRC outperforms the standalone EGC and MRC schemes by having lower Pout and Pt values. Hence, hybrid EGC-MRC exhibits enhanced potentials to mitigate multipath propagation at reduced system complexity.
Performance evaluation of different spectrum sensing techniques for realistic...ijwmn
In this paper, the performance assessment of five different detection techniques from spectrum sensing
perspective in cognitive radio networks is proposed and implemented using the realistic implementation
oriented model (R-model) with signal processing operations. The performance assessment of the different
sensing techniques in the existence of unknown or imprecisely known impulsive noise levels is done by
considering the signal detection in cognitive radio networks under a non-parametric multisensory detection
scenario. The examination focuses on performance comparison of basic spectrum sensing mechanisms as,
energy detection (ED) and cyclostationary feature detection (CSFD) along with the eigenvalue-based
detection methods namely, Maximum-minimum eigenvalue detection (MMED), Roy’s largest Root Test
(RLRT) which requires knowledge of the noise variance and Generalized Likelihood Ratio Test (GLRT)
which can be implemented as a test of the largest eigenvalues vs. Maximum-likelihood estimates a noise
variance. From simulation results it is observed that the detection performance of the GLRT method is
better than the other techniques in realistic implementation oriented model.
Negative image amplifier technique for performance enhancement of ultra wideb...IJECEIAES
The paper aims at designing of two stage cascaded ultra-wideband (UWB) low noise amplifier (LNA) by using negative image amplifier technique. The objective of this article is to show the performance improvement using negative image amplifier technique and realization of negative valued lumped elements into microstrip line geometry. The innovative technique to realize the negative lumped elements are carried out by using Richard’s Transformation and transmission line calculation. The AWR microwave office tool is used to obtain characteristics of UWB LNA design with hybrid microwave integrated circuit (HMIC) technology. The 2-stage cascaded LNA design using negative image amplifier technique achieves average gain of 23dB gain and low noise figure of less than 2dB with return loss less than -8dB for UWB 3-10GHz. The Proper bias circuit is extracted using DC characteristics of transistor at biasing point 2V, 20mA and discussed in detail with LNA layout. The negative image matching technique is applied for both input and output matching network. This work will be useful for all low power UWB wireless receiver applications.
Performance analysis and monitoring of various advanced digital modulation an...IJCNCJournal
To achieve better calculative performance in optical fiber communication and for simplicity of
implementation different digital modulation, detection and multiplexing techniques are used. These
techniques maximize the spectral efficiency. This paper reviews a tabular comparative analysis with 3D
graphical representation for different optical digital modulation formats and multiplexing techniques
within and beyond 400 Gb/s. In this particular article we survey about different parameters related to
digital fiber optic communication.
Powerful business model for fixed wireless data using outdoor antennas - PaperAndre Fourie
Paper presented at the 2nd Africa Radio Comms Conference in Johannesburg - Nov 2015
By Andre Fourie
The revenue that can be generated by an LTE base station is influenced by the quality of the signal received by the customer premise equipment (CPE). Most CPE come with omni-directional indoor antennas, but have provision for the connection to external antennas.
Substituting the indoor antennas for directional outdoor antennas has a marked effect on the data transfer speeds of the network. There are two reasons for this. Firstly, outdoor antennas are physically larger than their indoor counterparts and thus have a higher gain. The increase in antenna gain translates directly to an increase in received signal strength. The second advantage is that the outdoor antenna sits in an environment that has much better propagating properties than the indoor antenna. Tests have shown that data speeds 3-5 times faster are possible using external antennas compared to indoor antennas.
It is shown, using a primitive financial model that fairly large financial gains can be made by equipping CPE devices with external antennas.
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.
Implementation Cost Analysis of the Interpolator for the Wimax Technologyiosrjce
The design of the multirate filter (programmable) has been proposed which can be used in digital
transceivers that meets 802.16d/e (wimax) standard in the wireless communication system. Wimax is a
technology emerging in the wireless communication system in order to increase the broadband wireless internet
access. As there is wide spread need of the digital representation of the signal for the transmission and storage
which create the challenges in DSP [1]. In this paper, analysis of the implementation cost of interpolator for the
wimax technology, and cost of interpolator is analyzed on the basis of number of adders and multiplier. The
Filters are designed using the FDA (filters design and analysis) tool in MATLAB.
Advanced modulation coding schemes for an optical transceiver systems–based O...journalBEEI
This paper examines advanced modulation coding schemes for an optical transceiver systems–based optical wireless communication (OWC) channel model. These modulation techniquesinclude On-Off keying and return to zero (RZ)/non–return to zero (NRZ) coding. The signal power level against time and frequency spectral variations are measured. The max. Q factor and min. bit error rate (BER) are estimated and clarified for each modulation code scheme by using an optisystem simulation model. Transmission bit rates of up to 40 Gb/s can be achieved for possible distances up to 500 km with acceptable Q factor. The received power and max. Q factor are measured and clarified with OWC distance variations. The On-Off keying modulation code scheme resulted in better performance than the other modulation code schemes did.
Non-binary codes approach on the performance of short-packet full-duplex tran...IJECEIAES
This paper illustrates the enhancement of the performance of short-packet full-duplex (FD) transmission by taking the approach of non-binary low density parity check (NB-LDPC) codes over higher Galois field. For the purpose of reducing the impacts of self-interference (SI), high order of modulation, complexity, and latency decoder, a blind feedback process composed of channels estimation and decoding algorithm is implemented. In particular, this method uses an iterative process to simultaneously suppress SI component of FD transmission, estimate intended channel, and decode messages. The results indicate that the proposed technique provides a better solution than both the NB-LDPC without feedback and the binary LDPC feedback algorithms. Indeed, it can significantly improve the performance of overall system in two important factors, which are bit-error-rate (BER) and mean square error (MSE), especially in high order of modulation. The suggested algorithm also shows a robustness in reliability and power consumption for both short-packet FD transmissions and high order modulation communications.
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.
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.
PERFORMANCE OF WIMAX PHYSICAL LAYER WITH VARIATIONS IN CHANNEL CODING AND DIG...ijistjournal
The aim of this paper is to analyze the bit error rate (BER) performance of WiMAX physical layer with the implementation of different concatenated channel coding schemes under QAM and 16QAM digital modulations over realistic channel conditions (i.e. noise and multipath fading). In concatenated channel coding, the WiMAX system incorporates CRC-CC (Cyclic Redundancy Check and Convolutional) or RSCC (Reed-Solomon and Convolutional) encoder over an additative white gaussian noise (AWGN) and other multipath fading (Raleigh and Rician) channels. A segment of synthetic data is used for the analysis. Computer simulation results based on BER and signal to noise ratio (SNR) demonstrate that the performance of concatenated CRC-CC coded WiMAX system under QAM modulation is better as compared to RS-CC coded system over noisy and fading environments.
PERFORMANCE OF WIMAX PHYSICAL LAYER WITH VARIATIONS IN CHANNEL CODING AND DIG...ijistjournal
The aim of this paper is to analyze the bit error rate (BER) performance of WiMAX physical layer with the implementation of different concatenated channel coding schemes under QAM and 16QAM digital modulations over realistic channel conditions (i.e. noise and multipath fading). In concatenated channel coding, the WiMAX system incorporates CRC-CC (Cyclic Redundancy Check and Convolutional) or RSCC (Reed-Solomon and Convolutional) encoder over an additative white gaussian noise (AWGN) and other multipath fading (Raleigh and Rician) channels. A segment of synthetic data is used for the analysis. Computer simulation results based on BER and signal to noise ratio (SNR) demonstrate that the performance of concatenated CRC-CC coded WiMAX system under QAM modulation is better as compared to RS-CC coded system over noisy and fading environments.
Performance Improvement of IEEE 802.22 WRAN Physical LayerIOSR Journals
The spectrum available for the wireless services is limited, the increased demand of wireless
application has put a lot of limitations on the utilization of available radio spectrum. For the efficient spectrum
utilization for wireless application IEEE 802.22 standard i.e. WRAN (Wireless Regional Area Network) is
developed which is based on cognitive radio technique that senses the free available spectrum. It allows sharing
of geographically unused channels allocated to the TV Broadcast Service, without interference.
In this paper we are evaluating the performance of WRAN over physical layer with QPSK, 16-QAM
and 64-QAM modulation with Convolution coding with code rate of 1/2, 2/3, 3/4, 5/6 and obtaining the BER
curves for rician channel. Simulation is performed in MATLAB
Performance Improvement of IEEE 802.22 WRAN Physical LayerIOSR Journals
Abstract: The spectrum available for the wireless services is limited, the increased demand of wireless application has put a lot of limitations on the utilization of available radio spectrum. For the efficient spectrum utilization for wireless application IEEE 802.22 standard i.e. WRAN (Wireless Regional Area Network) is developed which is based on cognitive radio technique that senses the free available spectrum. It allows sharing of geographically unused channels allocated to the TV Broadcast Service, without interference. In this paper we are evaluating the performance of WRAN over physical layer with QPSK, 16-QAM and 64-QAM modulation with Convolution coding with code rate of 1/2, 2/3, 3/4, 5/6 and obtaining the BER curves for rician channel. Simulation is performed in MATLAB. Keywords - CC, CP, CR, OFDMA, PHY Layer, WRAN
Performance Improvement of IEEE 802.22 WRAN Physical LayerIOSR Journals
Abstract: The spectrum available for the wireless services is limited, the increased demand of wireless
application has put a lot of limitations on the utilization of available radio spectrum. For the efficient spectrum
utilization for wireless application IEEE 802.22 standard i.e. WRAN (Wireless Regional Area Network) is
developed which is based on cognitive radio technique that senses the free available spectrum. It allows sharing
of geographically unused channels allocated to the TV Broadcast Service, without interference.
In this paper we are evaluating the performance of WRAN over physical layer with QPSK, 16-QAM
and 64-QAM modulation with Convolution coding with code rate of 1/2, 2/3, 3/4, 5/6 and obtaining the BER
curves for rician channel. Simulation is performed in MATLAB.
Keywords - CC, CP, CR, OFDMA, PHY Layer, WRAN
Impulse Radio Ultra WideBand (IR-UWB) commu- nication has proven to be an important
technique for supporting high-rate, short-range, and low-power communication. In this paper, using
detailed models of typical IR-UWB transmitter and receiver structures, we model the energy
consumption per information bit in a single linkof an IR-UWB system, considering packet overhead,
retransmissions, and a Nakagami-m fading channel. Using this model, we minimize the energy
consumption per information bit by finding the optimum packet length and the optimum number of
RAKE fingers at the receiver for different transmission distances, using Differential Phase-shift keying
(DBPSK), Differential Pulse-position Modulation (DPPM) and On-off Keying (OOK), with coherent
and non-coherent detection. The increasing demand for wireless communication introduces efficient
spectrum utilization challenge. To address this challenge, cognitive radio (CR) is emerged as the key
technology; which enables opportunistic access to the spectrum. CR is a form of wireless
communication in which a transceiver can intelligently detect which communication channels are in
use and which are not, and instantly move into vacant channels while avoiding occupied ones..
Similar to ANALYTICAL PERFORMANCE EVALUATION OF AN LDPC CODED INDOOR OPTICAL WIRELESS COMMUNICATION SYSTEM (20)
Integrated Optics and Lightwave : An International Journaloptljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Lightwave : An International Journal ( OPTLJ )optljjournal
Integrated Optics and Lightwave : An International Journal ( OPTLJ )
http://airccse.com/optlj/index.html
contact mail : optljjournal@airccse.com
submit your research paper
http://airccse.com/submission/home.html
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
ANALYTICAL PERFORMANCE EVALUATION OF AN LDPC CODED INDOOR OPTICAL WIRELESS CO...optljjournal
Recently, indoor Optical Wireless (OW) connectivity has gained significant attention as a possible
alternative to tackle the problem of bottleneck access and as an improvement to ever more conventional RF
/ microwave connections. In indoor OW communication, OOK encoding is more widely used owing to its
effective usage of bandwidth and robustness to timing errors, given the fact that the power consumption is
less than PPM. The modulation format in this research work is Q-array PPM over lasers, with modulation
of power. The effects of the analysis are analyzed numerically in view of the amount of bit error (BER). It is
shown that, because of coding for 4PPM framework, the bit error performance is increased. For instance,
an LDPC-coded device with stable foundation radiation provides a important coding improvement of 5 to 6
dB over uncoded device at BER in the order of 10-8 and 10-12 respectively.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews
ANALYTICAL PERFORMANCE EVALUATION OF A MIMO FSO COMMUNICATION SYSTEM WITH DIR...optljjournal
MIMO FSO correspondence is examined as of late to build up a hearty correspondence connects within the
sight of atmospheric turbulence. In this paper an analytical approach is developed to assess the impact of
atmospheric turbulence on BER performance of a MIMO FSO communication system with Q-ary Pulse
Position Modulation (QPPM). Examination is exhibited to discover flag to clamor proportion at the yield
of an immediate location collector with optical power modulator under strong turbulent condition which is
modeled as gamma-gamma distribution. The outcomes demonstrate that the BER performance is
emphatically debased because of the impact of atmospheric turbulence
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews.
Integrated Optics and Light wave: An International Journal ( OPTLJ )optljjournal
Innovations in optical fiber technology are revolutionizing world communications. Newly developed Optical fibers and amplifiers allow direct transmission of high-speed signals over transcontinental distances without the need for electronic regeneration. Optical fibers find new applications in data processing. The impact of fiber materials, devices and systems on communications in the coming decades will create an abundance of primary literature and the need for up-to-date reviews
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
block diagram and signal flow graph representation
ANALYTICAL PERFORMANCE EVALUATION OF AN LDPC CODED INDOOR OPTICAL WIRELESS COMMUNICATION SYSTEM
1. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
1
ANALYTICAL PERFORMANCE EVALUATION OF AN
LDPC CODED INDOOR OPTICAL WIRELESS
COMMUNICATION SYSTEM
Dalia Barua1
and Bobby Barua2
1
Institute of Information Technology, Jahangirnagar University, Dhaka, Bangladesh
2
Department of EEE, Ahsanullah University of Science and
Technology, Dhaka, Bangladesh
ABSTRACT
Recently, indoor Optical Wireless (OW) connectivity has gained significant attention as a possible
alternative to tackle the problem of bottleneck access and as an improvement to ever more conventional RF
/ microwave connections. In indoor OW communication, OOK encoding is more widely used owing to its
effective usage of bandwidth and robustness to timing errors, given the fact that the power consumption is
less than PPM. The modulation format in this research work is Q-array PPM over lasers, with modulation
of power. The effects of the analysis are analyzed numerically in view of the amount of bit error (BER). It is
shown that, because of coding for 4PPM framework, the bit error performance is increased. For instance,
an LDPC-coded device with stable foundation radiation provides a important coding improvement of 5 to 6
dB over uncoded device at BER in the order of 10-8
and 10-12
respectively.
KEYWORDS
Bit error rate (BER),Indoor optical wireless (IOW), low density parity check (LDPC) code, on-off keying
(OOK), signal to noise ratio(SNR) ,Q-ary pulse position modulation (QPPM).
1. INTRODUCTION
Gfeller and Bapst initially introduced indoor optical wireless (OW) communication [1] in 1979,
and its implementations have actually reached households, workplaces and factories varying from
TV control to IrDA terminals on handheld electronic devices such as cell phones, video cameras,
digital assistants, and laptops[2-4]. Indoor OW communication is an attractive solution in the
ultraviolet and visible range, particularly in atmosphere settings where radio communication
experiences difficulties [5-6]. Modern indoor OW transmission techniques enable data-rates up to
25 Gbit/s [7-9]. LED lights, which are usually used for illumination purposes, relay data
concurrently and though handheld terminals do not fit with the connection point [10-11].
In real-world indoor systems, the consumer may travel inside a small coverage range, usually
equivalent to the size of a space or an aircraft cabin [12]. This may be difficult to have OW
exposure to a traveling user, because the optical rays are obscured by items inside the space [13-
14]. For narrower distances safe from environmental pollution such as fog, haze, snow and mist,
indoor optical wireless networks are defined as opposed to outdoor models. The failure in the
indoor connection only exists because of free space loss [15]. There are two simple wireless
2. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
2
optical indoor communication techniques: Direct sight line and diffused setup. The design of the
direct line of sight includes synchronization between the transmitter and the receiver in order to
maintain contact by transmitting optical signals from the transmitter to the receiver without any
reflection [16]. Such a network has greater power efficiency; reduced multipath dispersion and
lower path failure, and greater transmission speeds can be obtained.
A potential alternative is to install a narrow-beam and roof-mounted transmitter which is powered
by a tracking mechanism. The monitoring system rotates the transmitter and, with appropriate
modulation technique, guides the narrow optical beam from the transmitter to the handheld
receiver [17-18]. The key goal of this research work is to identify the best implemented
modulation method in diffused OW indoor systems. For this research LDPC code is used to
locate higher quality signal. The aim of this work is to establish the output analysis for Indoor
diffused OW System by defining better performing modulation strategies from OOK and 4-PPM.
Eventually, the study aims to increase the reliability of Indoor Diffused Optical Wireless System,
and LDPC code is used in comparison to both modulation strategies.
2. SYSTEM MODEL
Mobile
Terminal
Mobile
Terminal
Ceiling
Base station
Receiver Transmitter
ceiling
Multiplexer LDPC encoder
r=k/n
Inter leaver
mxn
Transmitter Receiver
LDPC Decoder
Demultiplexer
1
L
Users
Mobile Terminal Mobile Terminal
(b)
(a)
(c)
Receiver
De-Inter leaver
mxn
L
Users
1 :
:
Receiver
Figure 1: (a) Orientation (b) setup and (c) block diagram of an LDPC coded indoor wireless optical
communication system.
Figure 1 provides a schematic of a typical scenario for indoor OW communications. Mobile
terminals are permitted to travel within a room and need ties to a base station on the ceiling and
other mobile terminals to be created. For certain interfaces the reflective optical force is guided
into the receiver, while in others the emitted signal is allowed to bounce off surfaces in the space
diffusely. Infrared light sources are the channel's primary cause of noise which must be included
in the design of the network.
Moreover, the usable bandwidth may be high in certain guided wireless optical links, which
enables massive quantities of information to be transmitted, particularly in short-range
applications.
3. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
3
3. THEORETICAL ANALYSIS OF INDOOR OW COMMUNICATION SYSTEM
The principle can be expressed by the following equations for uncoded situation [19]:
𝑅𝑏=𝐵𝑙𝑜𝑔2 𝑀 (1)
𝑅𝑏=𝐵.
𝑙𝑜𝑔2 𝑀
𝑀
[For PPM] (2)
𝐵𝐸𝑅
𝑂𝑂𝐾=𝑒𝑟𝑓𝑐(
𝑀
2
.𝑄.(√𝑆𝑁𝑅
𝑀.𝑙𝑜𝑔2𝑀
2
))
(3)
𝐵𝐸𝑅
𝑃𝑃𝑀=𝑒𝑟𝑓𝑐(2.
𝑀−1
𝑙𝑜𝑔2𝑀
.𝑄.(
1
𝑀−1
√𝑆𝑁𝑅.𝑙𝑜𝑔2𝑀))
(4)
Bandwidth B is the first-null bandwidth, SNR is the electrical signal-to-noise ratio, and M is the
number of chips which make up a symbol in PPM or the number of power levels in an ASK. The
Q(x) function is set to:
𝑄(𝑥) =
1
√2𝜋
∫ 𝑒
−𝑢2
2
.𝑑𝑢
∞
𝑥
(5)
To the coded process, the reliability of the bit L(cj), (j=1,2, ... ,m) (cj is the jth
bit of the observed
symbol q binary representation c=(c1,c2, ... ,cm)) is calculated from the reliability of the symbol.
(6)
The N-receiver outputs in response to symbol q, indicated as Znq(n=1,2,…,N; q=1,2,…,Q), are
analyzed to assess authenticity of symbols (q) (q=1,2,…,Q) denoted by [20]
2
1
1 1 1
2 2
( )
N
M
s
N Q
nq nm
m
n nI
n q
E
Z I
Z
M
q
(7)
Probability of error is demonstrated as:
2
, 2
( )
1
( | ) exp
2
2
nq n
n q n
Z I
P Z I
(8)
: 0
: 1
exp
log
exp
j
j
c c
j
c c
q
L c
q
4. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
4
4. RESULTS AND DISCUSSION
By applying the analytical method, we try to evaluate the efficiency of uncoded and power-
efficient coded modulation scheme based on bit-interleaved coded modulation (BICM) with
LDPC code as component code, appropriate for use with OOK and Q-ary PPM in indoor OW
communication systems. Perhaps the coded modulation scheme enables very normal integration
of RF / microwave signals and translation to the optical domain, which could be a strong choice
for RF / microwave hybrid systems. In the presence of background radiation, the output effects of
Bit-error rate (BER) are tested with and without LDPC code.
At first the outputs of the bit error rate under uncoded and LDPC coded method have been
determined for two separate modulation schemes. Under direct diffuse system, we test the effects
of the bit error rate output with Q-ary PP and OOK modulation. The computational analyses are
conducted in LDPC decoder for up to 10 iterations, the scintillation effect is based on assuming a
diffused channel configuration and the usage of an optimal photon counting receiver. It is found
that if we induce Q-ary PPM as a modulation scheme for uncoded and LDPC coding rather than
OOk, the device output increases dramatically.
The specifications used for processing in this article are displayed in table 1 for the convenience
of the readers.
Table 1: Nominal Parameters for indoor OW Communication link
Parameter Name Value
Bit Rate, B
r
10 Gbps
Bandwidth, B 20 GHz
Modulation OOK and Q-PPM
Order of PPM, Q 4
Code word length 2048
Channel Type Diffused
PIN photodetector responsivity, Rd 0.7
Rytov variance, σ 0.1-0.8
Quantum efficiency, η 0.5
Operating wavelength, λ 1.55μm
5. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
5
Figure-2: BER against SNR plots for the indoor OW connectivity network with OOK and 4PPM
modulation.
Figure-2 reveals the BER against SNR plots for the indoor OW connectivity network with OOK
and 4PPM modulation. From the evaluation of the figure, it is evident that PPM is advantageous
over OOK for low-rate systems because it needs lower average power and is more reliable
towards optical noise, particularly near-baseband noise components.
Figure-3 BER versus SNR plots for indoor OW connectivity network with OOK modulation for both
uncoded and LDPC coding schemes.
Figure-3 demonstrates the plot of indoor OW connectivity network BER versus SNR with OOK
modulation under uncoded and LDPC coded condition. It is noted that the BER performance
under coded condition is much better than uncoded system.
0 2 4 6 8 10 12 14 16 18 20
10
-12
10
-10
10
-8
10
-6
10
-4
10
-2
10
0
snr
Ber
BER performance for Indoor Optical Communication
Uncoded OOK
Uncoded 4PPM
0 2 4 6 8 10 12 14 16 18 20
10
-12
10
-10
10
-8
10
-6
10
-4
10
-2
10
0
SNR
BER
BER performance for Indoor Optical Communication
Uncoded OOK
LDPCcoded OOK
6. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
6
Figure-4: BER against SNR plots with 4PP modulation for indoor OW communication networks for both
uncoded and LDPC coded application.
Figure-4 depicts BER against SNR plots with 4PP modulation under uncoded and LDPC coded
conditions for the indoor OW communication network. It is evident from the close examination
of the figure that the output of the BER is improved under a coded condition. It is also shown that
bit error is almost zero at a bit rate of 10-4
under coded condition.
Figure-5 BER toward SNR modules with OOK and 4PP modulation for indoor OW communication for
both uncoded and LDPC coded networks.
Figure-5 illustrates the BER versus SNR plots with OOK and 4PP modulation for the indoor OW
communication network. It is clear from the study of the figure that PPM is advantageous over
OOK for low-rate systems for both uncoded and coded conditions under the diffuse connection
channel model. Analysis shows that in this combination, we find a coding gain of almost 5 dB at
BER in the range of 10-12
.
0 2 4 6 8 10 12 14 16 18 20
10
-12
10
-10
10
-8
10
-6
10
-4
10
-2
10
0
SNR
BER
BER performance for Indoor Optical Communication
Uncoded 4PPM
LDPCcoded 4PPM
0 2 4 6 8 10 12 14 16 18 20
10
-12
10
-10
10
-8
10
-6
10
-4
10
-2
10
0
SNR
BER
BER performance for Indoor Optical Communication
Uncoded OOK
LDPCcoded OOK
Uncoded 4PPM
LDPCcoded 4PPM
7. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
7
5. CONCLUSIONS
Indoor OW networking has evolved as a technology that has the potential to bridge the last-mile
barrier of high-speed Internet access separating households and businesses. A comprehensive
analytical approach to analyze the degradation of the reliability of wireless optical links with
OOK and Q-ary PPM schemes is presented. Analysis reveals that PPM is advantageous over
OOK for low-rate systems, as it needs lower average power and is more resilient against optical
noise, particularly near-baseband noise. Elsewhere we introduce an analytical approach for
determining the efficiency of an uncoded and energy-efficient coded modulation scheme based on
bit-interleaved coded modulation (BICM) utilizing LDPC codes as component codes, suitable for
use in Q-ary PPM and OOK indoor OW networks. The results of the performance are assessed
numerically in terms of bit error rate (BER). It is observed that, due to coding for 4PPM
framework, the efficiency of bit error is increased. For reference, an LDPC-coded system with
constant background radiation provides a noticeable coding gain of 5 to 6 dB over uncoded
system at BER in the range of 10-8
and 10-12
respectively. Eventually, energy-efficient encoded
modulation mechanism focused on bit-interleaved coded modulation (BICM) for LDPC codes
offers excellent efficiency and seems to be easier to implement, as it includes only one LDPC
encoder / decoder. Overall the design and analysis proposed can solve the connectivity problem
of high speed indoor communication connections.
ACKNOWLEDGEMENTS
The authors would like to acknowledge with gratitude the support given to this research by the
Institute of Information Technology, Jahangirnagar University, Dhaka, Bangladesh and
Department of EEE, Ahsanullah University of Science and Technology.
REFERENCE
[1] Gfeller, F.R. and Bapst, U., (1979) “wireless In-house Data Communication via Diffused Radiation,”
Proceeding IEEE.
[2] Komine, T. and M. Nakagawa, (2004) “Fundamental analysis for visible light communication system
using LED lights,” IEEE Trans. OnConsumer Electronics, vol. 50, no. 1, pp.100–107.
[3] Bobby Barua, Tanzia Afrin Haque and Md. Rezwan Islam, (2012) “Error Probability Analysis of
Free-space Optical Links with Different Channel Model under Turbulent Condition”, International
Journal of Computer Science & Information Technology (IJCSIT) ,vol. 4, no. 1, pp.246-258 .
[4] Gonz´alez, O., S. Rodrguez, R. P´erez-Jim´enez, B. R. Mendoza, and A. Ayala, ( 2005) “Error
analysis of the simulated impulse response on indoor wireless optical channels using a Monte Carlo-
based ray-tracing algorithm,” IEEE Trans. on Communications, vol. 53, no. 1, pp. 199–204.
[5] Chen, C. H., C. L. Liu, C. C. Chiu, and T. M. Hu, (2006) “Ultrawide band channel calculation by
SBR/Image techniques for indoor communication,” J. of Electromagn. Waves and Appl., vol. 20, no.
1, pp.41–51.
[6] Havran, V., J. Bittner, and H.-P. Seidel, (2005) “Ray maps for global illumination,” Eurographics
Symposium on Rendering, pp.43–54.
[7] Chao Li, Xuebing Zhang, Eduward Tangdiongga, Xiaoyu Dai, Cheng-Ting Tsai, Huai-Yung Wang,
Yuanjiang Xiang, Gong-Ru Lin, Zizheng Cao, and Ton Koonen , (2019)”Cost-efficient half-duplex
10 Gbit/s all-optical indoor optical wireless communication enabled by a low-cost Fabry–Perot
laser/photodetector” Opt. Lett. vol.44, no. 5, pp. 1158-1161.
[8] A. T. Hussein, M. T. Alresheedi, and J. M. H. Elmirghani, (2015) “20 Gb/s Mobile Indoor Visible
Light Communication System Employing Beam Steering and Computer Generated Holograms,” J.
Light. Technol., vol. 33, no. 24, pp. 5242– 5260.
8. Integrated Optics and Lightwave : An International Journal(OPTLJ), Vol. 2, No.1 , 2020
8
[9] A. T. Hussein, M. T. Alresheedi, and J. M. H. Elmirghani, (2016) “25 Gbps mobile visible light
communication system employing fast adaptation techniques,” in International Conference on
Transparent Optical Networks.
[10] Cocheril, Y. and R. Vauzelle, (2007) “A new ray-tracing based wave propagation model including
rough surfaces scattering,” ProgressIn Electromagnetics Research, PIER 75, pp. 357–381.
[11] Liang, C., Z. Liu, and H. Di, (2008) “Study on the blockage of electromagnetic rays analytically,”
Progress in Electromagnetics Research B, vol. no. 1, pp.253–268.
[12] F. E. Alsaadi, M. A. Alhartomi, and J. M. H. Elmirghani, (2013) “Fast and efficient adaptation
algorithms for multi-gigabit wireless infrared systems,” J. Light. Technol., vol. 31, no. 23, pp. 3735–
3751.
[13] A. T. Hussein and J. M. H. Elmirghani, (2015) “10 Gbps Mobile Visible Light Communication
System Employing Angle Diversity, Imaging Receivers, and Relay Nodes,” J. Opt. Commun. Netw.,
vol. 7, no. 8, pp.718.
[14] S. H. Younus and J. M. H. Elmirghani, (2017) “WDM for high-speed indoor visible light
communication system,” in International Conference on Transparent Optical Networks.
[15] Ke Wang, Ampalavanapillai Nirmalathas, Christina Lim, and Efstratios Skafidas , (2015)
“Experimental demonstration of a novel indoor optical wireless localization system for high-speed
personal area networks” Opt. Lett. vol. 40, no. 7, pp. 1246-1249.
[16] Feng Feng, Paramin Sangwongngam, Grahame Faulkner, and Dominic O’Brien , (2019). “Wide field-
of-view optical broadcasting for bi-directional indoor optical wireless communications employing
PAM-4 modulation” Opt. Lett. vol. 44, no. 24, pp. 6009-6012.
[17] Dima Bykhovsky , (2018) “Coherence distance in indoor optical wireless communication channels”
Opt. Lett. vol. 43, no. 10 , pp.2248-2251.
[18] Jiayuan He, Jeonghun Lee, Tingting Song, Hongtao Li, Sithamparanathan Kandeepan, and Ke Wang
(2019), “Recurrent neural network (RNN) for delay-tolerant repetition-coded (RC) indoor optical
wireless communication systems” Opt. Lett. vol. 44, no. 15, pp. 3745-3748.
[19] Bobby Barua, and S. P. Majumder,( 2010) "Performance analysis of a LDPC coded multiple
input/multiple output free-space optical system with Q-ary pulse-position modulation", International
Conference on Electrical & Computer Engineering (ICECE 2010).
[20] Bobby Barua, and S. P. Majumder,( 2018) " Analytical Performance Evaluation of a MIMO FSO
Communication System with Direct Detection Optical Receivers Under Turbulent Condition",
Integrated Optics and Lightwave:An International Journal(OPTLJ), vol. 1, no.1, pp. 27-33.
AUTHORS
Dalia Barua is senior Lecturer in the Department of Computer Science and
Engineering at Ahsanullah Institute of Information and Communication Technology.
She received the B.Sc. in Computer Engineering from American International
University, Bangladesh in 2007 and Masters in Information Technology from
Institute of Information Technology, Jahangirnagar University in 2017. His research
interests include Optical Communication, Remote Sensing, Computer Networking
and Infra-red communications with 8 publications.
Bobby Barua is Professor (Full), Department of Electrical and Electronic
Engineering (EEE), Ahsanullah University of Science & Technology (AUST). He
received the B.Sc. in Electrical & Electronic Engineering (1st class with Honors)
from AUST in 2003 and M.Sc. in Electrical & Electronic Engineering (1st class
Honors) from BUET in 2008. In 2018, he obtained his Ph.D. degree in Electrical &
Electronic Engineering from BUET in 2018.He worked as research fellow at
Politecnico Di Milano, Italy. His research interests include Free space Optical
Communication Systems, Optical Fiber Communication Systems, Optical Networks,
Soliton propagation, Satellite Communications, Mobile and Infra-red communications with over 40
publications.