The technical challenges for communication engineers is the development of best performance wireless
networks with negligible amount of distortions. We have to consider multipath propagation attenuation and
radio spectrum inefficiency. Now a days, In MIMO (Multi Input Multi Output) systems there is a huge demand
for the networks with the high transmission rates and better quality of service which are having low PAPR ratio.
Instead of OFDMA, filter banks are used in massive MIMO to reduce the complexity. But they are error prone
to noise. This base paper discusses about PAPR reduction in MIMO systems using different precoding based
OFDM systems. Mainly, minimization of multi-antenna systems by controlling the transmission power and
reduction of PAPR using ZC (Zadoff-Chu) matrix transform.
Multi carrier equalization by restoration of redundanc y (merry) for adaptive...IJNSA Journal
This paper proposes a new blind adaptive channel shortening approach for multi-carrier systems. The
performance of the discrete Fourier transform-DMT (DFT-DMT) system is investigated with the proposed
DST-DMT system over the standard carrier serving area (CSA) loop1. Enhanced bit rates demonstrated
and less complexity also involved by the simulation of the DST-DMT system.
Intersymbol interference caused by multipath in band limited frequency selective time dispersive channels distorts the transmitted signal, causing bit error at receiver. ISI is the major obstacle to high speed data transmission over wireless channels. Channel estimation is a technique used to combat the intersymbol interference. The objective of this paper is to improve channel estimation accuracy in MIMO-OFDM system by using modified variable step size leaky Least Mean Square (MVSSLLMS) algorithm proposed for MIMO OFDM System. So we are going to analyze Bit Error Rate for different signal to noise ratio, also compare the proposed scheme with standard LMS channel estimation method.
Performance Analysis of MIMO-OFDM System Using QOSTBC Code Structure for M-PSKCSCJournals
MIMO-OFDM system has been currently recognized as one of the most competitive technology for 4G mobile wireless systems. MIMO-OFDM system can compensate for the lacks of MIMO systems and give play to the advantages of OFDM system. In this paper, a general Quasi orthogonal space time block code (QOSTBC) structure is proposed for multiple-input multiple-output–orthogonal frequency-division multiplexing (MIMO-OFDM) systems for 4X4 antenna configuration. The signal detection technology used in this paper for MIMO-OFDM system is Zero-Forcing Equalization (linear detection technique). In this paper the analysis of high level of modulations (i.e. M-PSK for different values of M) on MIMO-OFDM system is presented. Here AWGN and Rayleigh channels have been used for analysis purpose and their effect on BER for high data rates have been presented. The proposed MIMO-OFDM system with QOSTBC using 4X4 antenna configuration has better performance in terms of BER vs SNR than the other systems.
Performance analysis of DWT based OFDM over FFT based OFDM and implementing o...VLSICS Design
Growth in technology has led to unprecedented demand for high speed architectures for complex signal processing applications. In 4G wireless communication systems, bandwidth is a precious commodity, and service providers are continuously met with the challenge of accommodating more users with in a limited allocated bandwidth. To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. Recently DWT (Discrete wavelet transforms) is adopted in place of FFT (Fast Fourier transform) for frequency translation. Modulation schemes such as 16-QAM, 32-QAM, 64-QAM and 128-QAM (Quadrature amplitude modulation) have been used in the developed OFDM system for both DWT and FFT based model. In this paper we propose a DWT-IDWT based OFDM transmitter and receiver that achieve better performance in terms SNR and BER for AWGN channel. It proves all the wavelet families better over the IFFT-FFT implementation. The OFDM model is developed using Simulink, various test cases have been considered to verify its performance. The DWTOFDM using Lifting Scheme architecture is implemented on FPGA optimizing hardware, speed & cost. The wavelet filter used for this is Daubechies (9, 7) with N=2. The RTL code is written in Verilog-HDL and simulated in Modelsim. The design is then synthesized in Xilinx and implemented on Virtex5 FPGA board and the results were validated using ChipScope.
Multi carrier equalization by restoration of redundanc y (merry) for adaptive...IJNSA Journal
This paper proposes a new blind adaptive channel shortening approach for multi-carrier systems. The
performance of the discrete Fourier transform-DMT (DFT-DMT) system is investigated with the proposed
DST-DMT system over the standard carrier serving area (CSA) loop1. Enhanced bit rates demonstrated
and less complexity also involved by the simulation of the DST-DMT system.
Intersymbol interference caused by multipath in band limited frequency selective time dispersive channels distorts the transmitted signal, causing bit error at receiver. ISI is the major obstacle to high speed data transmission over wireless channels. Channel estimation is a technique used to combat the intersymbol interference. The objective of this paper is to improve channel estimation accuracy in MIMO-OFDM system by using modified variable step size leaky Least Mean Square (MVSSLLMS) algorithm proposed for MIMO OFDM System. So we are going to analyze Bit Error Rate for different signal to noise ratio, also compare the proposed scheme with standard LMS channel estimation method.
Performance Analysis of MIMO-OFDM System Using QOSTBC Code Structure for M-PSKCSCJournals
MIMO-OFDM system has been currently recognized as one of the most competitive technology for 4G mobile wireless systems. MIMO-OFDM system can compensate for the lacks of MIMO systems and give play to the advantages of OFDM system. In this paper, a general Quasi orthogonal space time block code (QOSTBC) structure is proposed for multiple-input multiple-output–orthogonal frequency-division multiplexing (MIMO-OFDM) systems for 4X4 antenna configuration. The signal detection technology used in this paper for MIMO-OFDM system is Zero-Forcing Equalization (linear detection technique). In this paper the analysis of high level of modulations (i.e. M-PSK for different values of M) on MIMO-OFDM system is presented. Here AWGN and Rayleigh channels have been used for analysis purpose and their effect on BER for high data rates have been presented. The proposed MIMO-OFDM system with QOSTBC using 4X4 antenna configuration has better performance in terms of BER vs SNR than the other systems.
Performance analysis of DWT based OFDM over FFT based OFDM and implementing o...VLSICS Design
Growth in technology has led to unprecedented demand for high speed architectures for complex signal processing applications. In 4G wireless communication systems, bandwidth is a precious commodity, and service providers are continuously met with the challenge of accommodating more users with in a limited allocated bandwidth. To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. Recently DWT (Discrete wavelet transforms) is adopted in place of FFT (Fast Fourier transform) for frequency translation. Modulation schemes such as 16-QAM, 32-QAM, 64-QAM and 128-QAM (Quadrature amplitude modulation) have been used in the developed OFDM system for both DWT and FFT based model. In this paper we propose a DWT-IDWT based OFDM transmitter and receiver that achieve better performance in terms SNR and BER for AWGN channel. It proves all the wavelet families better over the IFFT-FFT implementation. The OFDM model is developed using Simulink, various test cases have been considered to verify its performance. The DWTOFDM using Lifting Scheme architecture is implemented on FPGA optimizing hardware, speed & cost. The wavelet filter used for this is Daubechies (9, 7) with N=2. The RTL code is written in Verilog-HDL and simulated in Modelsim. The design is then synthesized in Xilinx and implemented on Virtex5 FPGA board and the results were validated using ChipScope.
Analyses and performance of techniques papr reduction for stbc mimo ofdm syst...ijwmn
An OFDM system is combined with multiple-input mult
iple-output (MIMO) in order to increase the
diversity gain and system capacity over the time va
riant frequency-selective channels. However, a maj
or
drawback of MIMO-OFDM system is that the transmitte
d signals on different antennas might exhibit high
peak-to-average power ratio (PAPR).In this paper, w
e present a PAPR analysis reduction of space-time-
block-coded (STBC) MIMO-OFDM system for 4G wireless
networks. Several techniques have been used to
reduce the PAPR of the (STBC) MIMOOFDM system: clip
ping and filtering, partial transmit sequence
(PTS) and selected mapping (SLM). Simulation result
s show that clipping and filtering provides a bette
r
PAPR reduction than the others methods and only SLM
technique conserve the PAPR reduction in
reception part of signal.
IMPROVEMENT OF LTE DOWNLINK SYSTEM PERFORMANCES USING THE LAGRANGE POLYNOMIAL...IJCNCJournal
To achieve a high speed data rate, higher spectral efficiency, improved services and low latency the 3rd
generation partnership project designed LTE standard (Long Term Evolution).the LTE system employs
specific technical as well the technical HARQ, MIMO transmission, OFDM Access or estimation technical.
In this paper we focus our study on downlink LTE channel estimation and specially the interpolation which
is the basis of the estimation of the channel coefficients. Thus, we propose an adaptive method for polynomial interpolation based on Lagrange polynomial. We perform the Downlink LTE system MIMO transmission then compare the obtained results with linear, Sinus Cardinal and polynomial Newton Interpolations. The simulation results show that the Lagrange method outperforms system performance in term of Block Error Rate (BLER) , throughput and EVN(%)vs. Signal to Noise Ratio (SNR).
A Network Selection Algorithm for supporting Drone Services in 5G Network Arc...University of Piraeus
Flying Ad-hoc Networks (FANETs) use 5G network access technologies to fulfill the requirements of their services. In this environment, Drone to Infrastructure (D2I) communication is supported, while each drone could use both Disaster Management (DM) and non-Disaster Management (nDM) services. Efficient network selection algorithms are required to satisfy the constraints of the used services, since the presence of DM services affects the importance of nDM services in situations where a natural disaster occurs. This paper proposes a network selection algorithm which is called Dynamic Trapezoidal Fuzzy Topsis with Adaptive Criteria Weights (DTFT-ACW). DTFT-ACW accomplishes the ranking of the candidate networks considering the importance of each service, as well as the weights of the corresponding selection criteria, as they are obtained with respect to the severity level of a natural disaster occurred. Interval-Valued Trapezoidal Fuzzy Numbers (IVTFN) are used for the criteria evaluation. Experimental results show that the suggested method outperforms existing algorithms by satisfying the constraints of DM services when a disaster becomes severe. Furthermore, DTFT-ACW eliminates the computational complexity of the network selection by considering past decisions.
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.
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.
A Hybrid PAPR Reduction Scheme for OFDM System ijmnct
Orthogonal frequency division multiplexing (OFDM) i
s considered as most efficient technique for future
wireless communication systems due to its higher sp
ectral bandwidth efficiency, robustness to frequenc
y
selective fading channels, etc. However, the succes
sful implementation of the OFDM system necessitates
several difficulties. The biggest disadvantage to w
ork with OFDM system is its high peak-to-average po
wer
ratio PAPR leadsto severe inter carrier interferenc
e, out-of-band radiation, and poor bit error rate
performance due to the nonlinearity of the high pow
er amplifier. In this paper, a novel hybrid techniq
ue is
proposed to reduce PAPR further and comparison has
been done with conventional techniques as well.
Simulated results are presentedconfirm theoretical
results.MATLAB 7.5 is used to simulate the results
for system parametersconsidered.
Bit Error Rate Performance of MIMO Spatial Multiplexing with MPSK Modulation ...ijsrd.com
Wireless communication is one of the most effective areas of technology development of our time. Wireless communications today covers a very wide array of applications. In this, we study the performance of general MIMO system, the general V-BLAST architecture with MPSK Modulation in Rayleigh fading channels. Based on bit error rate, we show the performance of the 2x2 schemes with MPSK Modulation in noisy environment. We also show the bit error rate performance of 2x2, 3x3, 4x4 systems with BPSK modulation. We see that the bit error rate performance of 2x2 systems with QPSK modulation gives us the best performance among other schemes analysed here.
A Novel Architecture for Different DSP Applications Using Field Programmable ...journal ijme
This paper presents a reconfigurable processor for different digital signal processing applications. The performance of the proposed architecture has been evaluated by taking different dsp applications like Low pass filter, high pass filter, finite impulse response (FIR) filter and FFT module. We designed the architecture of the processor and realizing the architecture using adder, multiplier, delay unit and validate it in the FPGA, which show that the hardware scheme is feasible for practical application. The experimental results clearly reveal the novelty of the architecture for dsp applications. This paper investigates the potential use of FPGAs for implementing efficient “Reconfigurable Processor” for different dsp applications. The proposed processor is based on parallel re-configurable which is implemented on FPGA. FPGAs have become an important component for implementing these functions with respect to cost, performance and flexibility. The general purpose SPARTAN 3AN FPGA kit has been employed for developing reconfigurable processor, with all the coding done using the hardware description language VERILOG.
Performance Analysis of Various Symbol Detection Techniques in Wireless MIMO ...IOSR Journals
Wireless communication is one of the most effective areas of technology development of our time.
Wireless communications today covers a very wide array of applications. In this paper, we study the
performance of general MIMO system, the performance of Zero Forcing (ZF), Linear Least Square Estimator
(LLSE), V-BLAST/ZF, V-BLAST/LLSE of 4x4, 4x6 & 4x8 with 4-QAM & 16-QAM modulation in i i d Rayleigh
fading channel. We seen that SER performance of 4x8 antennas and 4-QAM modulation scheme outperforms
others. Result shows that for higher modulation schemes SER performance degrades as well as SER
performance increases for higher no of receiver antennas
Finite Element Simulation of Steel Plate Concrete Beams subjected to ShearIJERA Editor
In a test series ofSteel plate Concrete (SC) beams conducted by the authorsto determine the minimum shear
reinforcement ratio, complex structural behavior of the tested beams was observed, including shear cracking
occurred within the concrete in the web and bond-slip failure of the bottom steel plate of the beam due to
insufficient shear reinforcement ratio (Qin et al. 2015).This paper focuses on finite element simulation (FEM) of
the SC beams withemphasis on shear and bond-slip behavior. A new constitutive model is proposed to account for
the bond-slip behavior of steel plates. Also, the Cyclic Softened Membrane Model proposed by Hsu and Mo
(2010)is utilized to simulate the shear behavior of concrete with embedded shear reinforcement. Both constitutive
models areimplemented into a finite element analysis program based on the framework of OpenSees (2013).The
proposed FEM is able to capturethe behavior of the tested SC beams.
Investigation of Mechanical Properties in Polyester and Phenyl-ester Composit...IJERA Editor
The purpose of the study is to utilize the chicken feather and finding the mechanical properties of the chicken feather reinforcing with polyester and phenyl ester. The bi-directional CFF reinforced composites were produced with phenyl ester and polyester resins with fiber reinforced composites, the chicken feather fibers (CFF) were cleaned, tested to know the mechanical properties and tensile behavior. It is found that the compressive properties of the CFF reinforced composites are significantly better than the control composites, however, the tensile and the flexural properties are determine by tensile, compressive, and flexural test. The CFF reinforced composite have potential applications due to its improved behavior and structural applications. The poultry waste can be utilized and used in any engineering applications, and it will be preferred due to low-cost and superior characteristics and the most importantly it will not cause ecological and health problems.
Cloud Computing: A study of cloud architecture and its patternsIJERA Editor
Cloud computing is a general term for anything that involves delivering hosted services over the Internet. Cloud computing is a paradigm shift following the shift from mainframe to client–server in the early 1980s. Cloud computing can be defined as accessing third party software and services on web and paying as per usage. It facilitates scalability and virtualized resources over Internet as a service providing cost effective and scalable solution to customers. Cloud computing has evolved as a disruptive technology and picked up speed with the presence of many vendors in cloud computing space. The evolution of cloud computing from numerous technological approaches and business models such as SaaS, cluster computing, high performance computing, etc., signifies that the cloud IDM can be considered as a superset of all the corresponding issues from these paradigms and many more. In this paper we will discuss Life cycle management, Cloud architecture, Pattern in Cloud IDM, Volatility of Cloud relations.
Development of a Taguchi-based framework for optimizing two quality character...IJERA Editor
A framework based on Taguchi parameter design was developed and successfully demonstrated to optimize two
quality characteristics- surface roughness and angular accuracy in Wire Electrical Discharge Machining (WEDM)
process. An orthogonal array (OA)L9was used in the Taguchi experiment design for four controllable
factors, each with three levels. With one non-controllable factor investigated, 18 experiments were conducted in
the Taguchi-based experiment setting, compared to 34 (=81) parameter combination as required by a traditional
DOE setting. Conducted for the two response variables, Taguchi experiments from the case study gave the
optimal combination of pulse on time at 9μs (A1), feed rate at 35 in/min (B2), voltage at 8v (C2), and wire
tension at 165g (D3) for surface roughness optmization, and pulse on time at 13μs (A3), feed rate at 35 in/min
(B2), voltage at 8v (C2), and wire tension at 160g (D2) for angular accuracy optmization. This optimal parameter
setting combination was verified through a confirmation run that confirms the optimal quality responses of
126.1μin for surface roughness and 0.024º for angular accuracy. This research ultimately showed the dual
output variable improvement and the framework established itself as a means to solve similar problems in other
machining applications. The developed framework can serve as guidance for researchers to obtain multivariable
optimal setting in a systematic way.
Study of Surface Roughness Characteristics of Drilled Hole in Glass Fiber Rei...IJERA Editor
Now-a-days glass fiber-reinforced plastics (GFRP) are always applicable in variety of engineering applications.
It is used in aerospace, automotive and aircraft industries due to their well known properties. Milling of GFRP
composite materials is very difficult due to its heterogeneity and the number of troubles like as surface
delamination during machining affects uniqueness of the material and the machining parameters. Present paper
focuses the experimental details to find out delamination factor on GFRP composite laminates by using
Taguchi‟s DOE L9 orthogonal array. The main objective of the present work is to optimize the process
parameters in the drilling of GFRP composite using Taguchi DOE and to find the significance of each process
parameter using ANOVA. As far as the effect of input factors are considered, the factors drilled material and
spindle speed both have nearly predominant influence on the delamination factor of drilled holes on GFRP
composite by using CNC milling process.
Analyses and performance of techniques papr reduction for stbc mimo ofdm syst...ijwmn
An OFDM system is combined with multiple-input mult
iple-output (MIMO) in order to increase the
diversity gain and system capacity over the time va
riant frequency-selective channels. However, a maj
or
drawback of MIMO-OFDM system is that the transmitte
d signals on different antennas might exhibit high
peak-to-average power ratio (PAPR).In this paper, w
e present a PAPR analysis reduction of space-time-
block-coded (STBC) MIMO-OFDM system for 4G wireless
networks. Several techniques have been used to
reduce the PAPR of the (STBC) MIMOOFDM system: clip
ping and filtering, partial transmit sequence
(PTS) and selected mapping (SLM). Simulation result
s show that clipping and filtering provides a bette
r
PAPR reduction than the others methods and only SLM
technique conserve the PAPR reduction in
reception part of signal.
IMPROVEMENT OF LTE DOWNLINK SYSTEM PERFORMANCES USING THE LAGRANGE POLYNOMIAL...IJCNCJournal
To achieve a high speed data rate, higher spectral efficiency, improved services and low latency the 3rd
generation partnership project designed LTE standard (Long Term Evolution).the LTE system employs
specific technical as well the technical HARQ, MIMO transmission, OFDM Access or estimation technical.
In this paper we focus our study on downlink LTE channel estimation and specially the interpolation which
is the basis of the estimation of the channel coefficients. Thus, we propose an adaptive method for polynomial interpolation based on Lagrange polynomial. We perform the Downlink LTE system MIMO transmission then compare the obtained results with linear, Sinus Cardinal and polynomial Newton Interpolations. The simulation results show that the Lagrange method outperforms system performance in term of Block Error Rate (BLER) , throughput and EVN(%)vs. Signal to Noise Ratio (SNR).
A Network Selection Algorithm for supporting Drone Services in 5G Network Arc...University of Piraeus
Flying Ad-hoc Networks (FANETs) use 5G network access technologies to fulfill the requirements of their services. In this environment, Drone to Infrastructure (D2I) communication is supported, while each drone could use both Disaster Management (DM) and non-Disaster Management (nDM) services. Efficient network selection algorithms are required to satisfy the constraints of the used services, since the presence of DM services affects the importance of nDM services in situations where a natural disaster occurs. This paper proposes a network selection algorithm which is called Dynamic Trapezoidal Fuzzy Topsis with Adaptive Criteria Weights (DTFT-ACW). DTFT-ACW accomplishes the ranking of the candidate networks considering the importance of each service, as well as the weights of the corresponding selection criteria, as they are obtained with respect to the severity level of a natural disaster occurred. Interval-Valued Trapezoidal Fuzzy Numbers (IVTFN) are used for the criteria evaluation. Experimental results show that the suggested method outperforms existing algorithms by satisfying the constraints of DM services when a disaster becomes severe. Furthermore, DTFT-ACW eliminates the computational complexity of the network selection by considering past decisions.
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.
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.
A Hybrid PAPR Reduction Scheme for OFDM System ijmnct
Orthogonal frequency division multiplexing (OFDM) i
s considered as most efficient technique for future
wireless communication systems due to its higher sp
ectral bandwidth efficiency, robustness to frequenc
y
selective fading channels, etc. However, the succes
sful implementation of the OFDM system necessitates
several difficulties. The biggest disadvantage to w
ork with OFDM system is its high peak-to-average po
wer
ratio PAPR leadsto severe inter carrier interferenc
e, out-of-band radiation, and poor bit error rate
performance due to the nonlinearity of the high pow
er amplifier. In this paper, a novel hybrid techniq
ue is
proposed to reduce PAPR further and comparison has
been done with conventional techniques as well.
Simulated results are presentedconfirm theoretical
results.MATLAB 7.5 is used to simulate the results
for system parametersconsidered.
Bit Error Rate Performance of MIMO Spatial Multiplexing with MPSK Modulation ...ijsrd.com
Wireless communication is one of the most effective areas of technology development of our time. Wireless communications today covers a very wide array of applications. In this, we study the performance of general MIMO system, the general V-BLAST architecture with MPSK Modulation in Rayleigh fading channels. Based on bit error rate, we show the performance of the 2x2 schemes with MPSK Modulation in noisy environment. We also show the bit error rate performance of 2x2, 3x3, 4x4 systems with BPSK modulation. We see that the bit error rate performance of 2x2 systems with QPSK modulation gives us the best performance among other schemes analysed here.
A Novel Architecture for Different DSP Applications Using Field Programmable ...journal ijme
This paper presents a reconfigurable processor for different digital signal processing applications. The performance of the proposed architecture has been evaluated by taking different dsp applications like Low pass filter, high pass filter, finite impulse response (FIR) filter and FFT module. We designed the architecture of the processor and realizing the architecture using adder, multiplier, delay unit and validate it in the FPGA, which show that the hardware scheme is feasible for practical application. The experimental results clearly reveal the novelty of the architecture for dsp applications. This paper investigates the potential use of FPGAs for implementing efficient “Reconfigurable Processor” for different dsp applications. The proposed processor is based on parallel re-configurable which is implemented on FPGA. FPGAs have become an important component for implementing these functions with respect to cost, performance and flexibility. The general purpose SPARTAN 3AN FPGA kit has been employed for developing reconfigurable processor, with all the coding done using the hardware description language VERILOG.
Performance Analysis of Various Symbol Detection Techniques in Wireless MIMO ...IOSR Journals
Wireless communication is one of the most effective areas of technology development of our time.
Wireless communications today covers a very wide array of applications. In this paper, we study the
performance of general MIMO system, the performance of Zero Forcing (ZF), Linear Least Square Estimator
(LLSE), V-BLAST/ZF, V-BLAST/LLSE of 4x4, 4x6 & 4x8 with 4-QAM & 16-QAM modulation in i i d Rayleigh
fading channel. We seen that SER performance of 4x8 antennas and 4-QAM modulation scheme outperforms
others. Result shows that for higher modulation schemes SER performance degrades as well as SER
performance increases for higher no of receiver antennas
Finite Element Simulation of Steel Plate Concrete Beams subjected to ShearIJERA Editor
In a test series ofSteel plate Concrete (SC) beams conducted by the authorsto determine the minimum shear
reinforcement ratio, complex structural behavior of the tested beams was observed, including shear cracking
occurred within the concrete in the web and bond-slip failure of the bottom steel plate of the beam due to
insufficient shear reinforcement ratio (Qin et al. 2015).This paper focuses on finite element simulation (FEM) of
the SC beams withemphasis on shear and bond-slip behavior. A new constitutive model is proposed to account for
the bond-slip behavior of steel plates. Also, the Cyclic Softened Membrane Model proposed by Hsu and Mo
(2010)is utilized to simulate the shear behavior of concrete with embedded shear reinforcement. Both constitutive
models areimplemented into a finite element analysis program based on the framework of OpenSees (2013).The
proposed FEM is able to capturethe behavior of the tested SC beams.
Investigation of Mechanical Properties in Polyester and Phenyl-ester Composit...IJERA Editor
The purpose of the study is to utilize the chicken feather and finding the mechanical properties of the chicken feather reinforcing with polyester and phenyl ester. The bi-directional CFF reinforced composites were produced with phenyl ester and polyester resins with fiber reinforced composites, the chicken feather fibers (CFF) were cleaned, tested to know the mechanical properties and tensile behavior. It is found that the compressive properties of the CFF reinforced composites are significantly better than the control composites, however, the tensile and the flexural properties are determine by tensile, compressive, and flexural test. The CFF reinforced composite have potential applications due to its improved behavior and structural applications. The poultry waste can be utilized and used in any engineering applications, and it will be preferred due to low-cost and superior characteristics and the most importantly it will not cause ecological and health problems.
Cloud Computing: A study of cloud architecture and its patternsIJERA Editor
Cloud computing is a general term for anything that involves delivering hosted services over the Internet. Cloud computing is a paradigm shift following the shift from mainframe to client–server in the early 1980s. Cloud computing can be defined as accessing third party software and services on web and paying as per usage. It facilitates scalability and virtualized resources over Internet as a service providing cost effective and scalable solution to customers. Cloud computing has evolved as a disruptive technology and picked up speed with the presence of many vendors in cloud computing space. The evolution of cloud computing from numerous technological approaches and business models such as SaaS, cluster computing, high performance computing, etc., signifies that the cloud IDM can be considered as a superset of all the corresponding issues from these paradigms and many more. In this paper we will discuss Life cycle management, Cloud architecture, Pattern in Cloud IDM, Volatility of Cloud relations.
Development of a Taguchi-based framework for optimizing two quality character...IJERA Editor
A framework based on Taguchi parameter design was developed and successfully demonstrated to optimize two
quality characteristics- surface roughness and angular accuracy in Wire Electrical Discharge Machining (WEDM)
process. An orthogonal array (OA)L9was used in the Taguchi experiment design for four controllable
factors, each with three levels. With one non-controllable factor investigated, 18 experiments were conducted in
the Taguchi-based experiment setting, compared to 34 (=81) parameter combination as required by a traditional
DOE setting. Conducted for the two response variables, Taguchi experiments from the case study gave the
optimal combination of pulse on time at 9μs (A1), feed rate at 35 in/min (B2), voltage at 8v (C2), and wire
tension at 165g (D3) for surface roughness optmization, and pulse on time at 13μs (A3), feed rate at 35 in/min
(B2), voltage at 8v (C2), and wire tension at 160g (D2) for angular accuracy optmization. This optimal parameter
setting combination was verified through a confirmation run that confirms the optimal quality responses of
126.1μin for surface roughness and 0.024º for angular accuracy. This research ultimately showed the dual
output variable improvement and the framework established itself as a means to solve similar problems in other
machining applications. The developed framework can serve as guidance for researchers to obtain multivariable
optimal setting in a systematic way.
Study of Surface Roughness Characteristics of Drilled Hole in Glass Fiber Rei...IJERA Editor
Now-a-days glass fiber-reinforced plastics (GFRP) are always applicable in variety of engineering applications.
It is used in aerospace, automotive and aircraft industries due to their well known properties. Milling of GFRP
composite materials is very difficult due to its heterogeneity and the number of troubles like as surface
delamination during machining affects uniqueness of the material and the machining parameters. Present paper
focuses the experimental details to find out delamination factor on GFRP composite laminates by using
Taguchi‟s DOE L9 orthogonal array. The main objective of the present work is to optimize the process
parameters in the drilling of GFRP composite using Taguchi DOE and to find the significance of each process
parameter using ANOVA. As far as the effect of input factors are considered, the factors drilled material and
spindle speed both have nearly predominant influence on the delamination factor of drilled holes on GFRP
composite by using CNC milling process.
A report on Groundwater quality studies in Malwa region of Punjab, MUKTSARIJERA Editor
Punjab is the most cultivated state in India with the highest consumption of fertilizers. Muktsar district is one of them. Economy of the district is based on the Agriculture crops and 80% population of the district is engaged in Agriculture. Sri Muktsar Sahib is situated in the cotton belt of Punjab. Paddy, Wheat, Sugarcane, Oilseeds, Pulses and vegetables are also cultivated in this area. This paper highlights the analysis of groundwater quality parameters and compares its suitability for irrigation and drinking purpose. Water samples were collected from hand-pumps at different depth in October 2010. . Water samples were analysed for almost all major cations, anions, dissolved heavy metals and turbidity. parameters like total hardness, EC, magnesium ratio, were calculated on the basis of chemical data. A questionnaire was also used to investigate perception of villagers on taste and odour. The heavy metals studied in industrial area of Muktsar were Mercury, arsenic and lead. Comparison of the concentration of the chemical constituents with WHO (world health organization) drinking water standards of 2004 , ICMR limits and various classifications show that present status of groundwater in Muktsar is not suitable for drinking. Higher totalhardness (TH) and total dissolved solids at numerous places indicate the unsuitability of groundwater for drinking and irrigation. Results obtained in this forms baseline data for the utility of groundwater. No clear correlation between the quality parameters studied here and perceived quality in terms of satisfactory taste response were obtained at electrical conductivity values higher than the threshold minimum acceptable value.
Wear and Corrosion Study of Sputtered Zirconium thin films on SS316L for Wind...IJERA Editor
The Aim of this study is to observe the Wear and Corrosion behavior of Zirconium coated 316L stainless steel. After polishing, SS316L was coated with Zirconium employing DC sputtering process (a technique of physical vapor deposition).Structure characterization techniques including Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) were utilized to investigate the microstructure and crystallinity of the coating. Salt spray test was performed by spraying Sodium chloride in order to determine corrosion resistance behavior of the coated sample. Pin on disc wear test was performed by hardened and tempered EN31 steel pin in order to determine and compare the Wear resistance behavior of Coated and uncoated samples. The Objective is to recommend the zirconium coated Stainless steel SS316L can be a choice for Off-shore wind mills where the shafts undergo Wear and corrosion problems.
A Novel Approaches For Chromatic Squander Less Visceral Coding Techniques Usi...IJERA Editor
Recent advances in video capturing and display technologies, along with the exponentially increasing demand of
video services, challenge the video coding research community to design new algorithms able to significantly
improve the compression performance of the current H.264/AVC standard. This target is currently gaining
evidence with the standardization activities in the High Efficiency Video Coding (HEVC) project. The distortion
models used in HEVC are mean squared error (MSE) and sum of absolute difference (SAD). However, they are
widely criticized for not correlating well with perceptual image quality. The structural similarity (SSIM) index
has been found to be a good indicator of perceived image quality. Meanwhile, it is computationally simple
compared with other state-of-the-art perceptual quality measures and has a number of desirable mathematical
properties for optimization tasks. We propose a perceptual video coding method to improve upon the current
HEVC based on an SSIM-inspired divisive normalization scheme as an attempt to transform the DCT domain
frame prediction residuals to a perceptually uniform space before encoding.
Based on the residual divisive normalization process, we define a distortion model for mode selection and show
that such a divisive normalization strategy largely simplifies the subsequent perceptual rate-distortion
optimization procedure. We further adjust the divisive normalization factors based on local content of the video
frame. Experiments show that the scheme can achieve significant gain in terms of rate-SSIM performance and
better visual quality when compared with HEVC
A Study on Relationship between Employee Satisfaction and Its DeterminantsIJERA Editor
Satisfaction refers to the level of fulfillment of one needs, wants and desire. Satisfaction
dependsbasicallyuponwhatanindividual wants from the world, and what he gets. Employee satisfaction is a
measure of how happy workers are with their job and working environment and may be many factors affecting
the organizational effectiveness and one of them is the employee satisfaction. Effective organizations should
have a culture that encourages the employee satisfaction. Many measures support that employee satisfaction is a
factor in employee motivation, employee goal achievement and positive employee morale in the work place. So
the present study to explain the relationship between employee satisfaction and its determinants by using
statistical tools.
Spectroscopic and Physical Properties of Mn2+ spin probe in RO-P2O5-ZnO-Pb3O4...IJERA Editor
RO-P2O5-ZnO-Pb3O4 (R=Li, Na and K) glasses containing 0.1concentrations of MnO have been prepared. The structural, optical and physical properties of prepared glasses are studied by XRD, UV-Visible, EPR and FTIR techniques. The nature of local symmetry and structural information of the neighboring atoms of dopant ions (Mn2+) in the host matrix have been understood by evaluating the crystal field strength (Dq) and Racah (B & C) parameters. The combined analysis of optical absorption and EPR spectroscopy has indicated that the manganese ions exist in Mn2+ (in octahedral) local coordination sites. FTIR results showed that PO4 are the main structural unit of the glass system and the manganese ions are located in the glass matrix network.
Ultra Low Power Design and High Speed Design of Domino Logic CircuitIJERA Editor
The tremendous success of the low-power designs of VLSI circuits over the past 50 years has significant change
in our life style. Integrated circuits are everywhere from computers to automobiles, from cell phones to home
appliances. Domino logic is a CMOS based evolution of the dynamic logic techniques based on either PMOS or
NMOS transistors. Dynamic logic circuits are used for their high performance, but their high noise and
extensive leakage has caused some problems for these circuits. Dynamic CMOS circuits are inherently less
resistant to noise than static CMOS circuits. In this paper we proposed different domino logic styles which
increases performance compared to existing domino logic styles. According to the simulations in cadence
virtuoso 65nm CMOS process, the proposed circuit shows the improvement of up thirty percent compared
existing domino logics.
Synthesis, Characterization and Electrical Properties of Polyaniline Doped wi...IJERA Editor
The polyaniline were prepared by using different inorganic and organic acids via oxidative polymerization
method. The prepared samples were characterized by FTIR, the peaks are found to be at 507 cm˗1, 592 cm˗1, 798
cm˗1, 1138 cm˗1, 1244 cm˗1, 1302 cm˗1, 1471 cm˗1 and 1556 cm˗1. These predominant peaks may be
confirming the formation of polyaniline. The structural analysis was studied by employing XRD; found that
polyaniline is amorphous in nature. The SEM studies reveal that they are agglomerated, irregular and size of
these grain increases with increasing amount of polyaniline with different organic and inorganic acids. The dc
conductivity (dc) as a function of temperature (T) for polyaniline is studied in the temperature range from 30 to
1600C. At higher temperature it is found that conductivity increases because of hopping of polarons from one
localized states to another localized states. The ac conductivity of polyaniline was prepared by oxalic acid show
high conductivity at 106 Hz. This is due to the space charge polarization and electrode polarizations.
Implementation of RTOS on STM32F4 Microcontroller to Control Parallel Boost f...IJERA Editor
The DC-DC converter is operated with pulse width modulation (PWM) and controlled by modifying duty cycle.
The PWM is easy developed on microcontroller system, but the problem become complex when some control
algorithm implemented to determine duty cycle value. Multitasking is needed to handle sensor, control algorithm
and user interface system. This paper discusses the application of Real Time Operating System (RTOS) to
handle multitasking process on STM32F407 ARM Cortex M4 microcontroller to control parallel boost converter
with load sharing algorithm for photovoltaic (PV) battery charging application. The first OS task is to run MPPT
to get maximum energy from PV. This first OS task is implemented to control the first boost converter. Then,
The second OS task to run fuzzy logic controller to control battery charging current with load sharing energy.
This second OS task is task implemented to control second boost converter. The measurement of current and
voltage of both converter side, display and user interface system also handled with OS task. As the result, each
designed task could run well with recommended OS task priority for MPPT and Fuzzy is IRQ task and for
TFT_LCD_displayosPriorityAboveNormal.
Experimental Characterization of Carbon Fibre T700 / Epoxy towpreg for Space ...IJERA Editor
This document covers detailed experimental characterization of Carbon Fibre T 700/Epoxy towpreg.The
experimental characterization of carbon fibre T 700/Epoxy towpreg composite material is necessary required for
generation of mechanical properties data for analysis, design, and fabrication of structural components using
that material and for quality control of the material. The testing of composite materials offers unique surprises
because of the special characteristics of composites. Factors not considered important in metals testing are very
important in testing composites. For example, composites are anisotropic, with properties that depend on the
direction in which they are tested. Speed must be carefully monitored at the time of testing of specimens and
also fiber content, void content, specimen conditioning (drying, storage, etc) have important effects on material
properties.
In order to design composite products, a thorough experimental characterization of carbon fibre T 700 / Epoxy
towpreg composite material and its behaviour is necessary.
A Stochastic Model by the Fourier Transform of Pde for the Glp - 1IJERA Editor
The peptide hormone glucagon like peptide GLP -1 has most important actions resulting in glucose lowering
along with weight loss in patients with type 2 diabetes. As a peptide hormone, GLP -1 has to be administered by
injection. A few small-molecule agonists to peptide hormone receptors have been described.
Here we develop a model for credit risk based on a model with stochastic eigen values called principal
component stochastic covariance.
Survey on Mobile Based Telemedicine System for Patient Monitoring and Diagnos...IJERA Editor
Recently remote health care has been a key issue to look after. As Sikkim is a hilly area suffering from transportation and inadequate medical facilities. Therefore, this survey on telemedicine system provides sufficient ideas for remote health diagnosis and monitoring in remote of Sikkim. As per the health personalities the various chronic diseases are diagnosed and treated with the human parameters such as ECG, SpO2, temperature, and blood pressure. These psychological signs are diagnosed in remote hospitals and PHCs and all physiological signs will be immediately transmitted to remote medical server through both cellular networks and internet. Also data can be transmitted to a family member’s mobile phone or doctor’s phone 3G and 4G networks. As Sikkim has 7 major hospitals and 24 PHCs, so one major hospital such as CRH Manipal or STNM can be chosen as a remote server unit and all the information through advance wireless communication module is received in this unit and patient health status can be diagnosed. As this hilly place lacks in medical facilities in remote places due to in educate knowledge of telemedicine system. This paper discuss about the recent trends in telemedicine for a small state. This paper is discussed in order to give 24*7 medical facilities in every corner of Sikkim. This paper also discusses the telemedicine system for normal and emergency condition. As this telemedicine is not a new technology, it’s an existing technology this paper discuss the advancement in such technology to provide better medical service for remote places.
A case study on Machine scheduling and sequencing using Meta heuristicsIJERA Editor
Modern manufacturing systems are constantly increasing in complexity and become more agile in nature such
system has become more crucial to check feasibility of machine scheduling and sequencing because effective
scheduling and sequencing can yield increase in productivity due to maximum utilization of available resources
but when number of machine increases traditional scheduling methods e.g. Johnson‟s ,rule is becomes in
effective Due to the limitations involved in exhaustive enumeration, for such problems meta-heuristics has
become greater choice for solving NP hard problems because of their multi solution and strong neighbourhood
search capability in a reasonable time.
Multi-carrier Equalization by Restoration of RedundancY (MERRY) for Adaptive ...IJNSA Journal
This paper proposes a new blind adaptive channel shortening approach for multi-carrier systems. The performance of the discrete Fourier transform-DMT (DFT-DMT) system is investigated with the proposed DST-DMT system over the standard carrier serving area (CSA) loop1. Enhanced bit rates demonstrated and less complexity also involved by the simulation of the DST-DMT system.
Capacity Enhancement of MIMO-OFDM System in Rayleigh Fading ChannelIOSR Journals
MIMO-OFDM system in Rayleigh Fading Channel is very popular technique for mobile
communication now a day’s for research. Here we want increase the capacity of MIMO-OFDM of system by
using adaptive modulation, Algebraic Space-Time Codes (ASTC) encoder for MIMO Systems are based on
quaternion algebras .we found that ergodic capacity has some limitation which reduce the system’s
performance to overcome this we use ASTC code . ASTC code are full rank, full rate and non vanishing constant
minimum determinant for increasing spectral efficiency and reducing Peak to Average Power Ratio (PAPR) .
Capacity Enhancement of MIMO-OFDM System in Rayleigh Fading ChannelIOSR Journals
Abstract: MIMO-OFDM system in Rayleigh Fading Channel is very popular technique for mobile communication now a day’s for research. Here we want increase the capacity of MIMO-OFDM of system by using adaptive modulation, Algebraic Space-Time Codes (ASTC) encoder for MIMO Systems are based on quaternion algebras .we found that ergodic capacity has some limitation which reduce the system’s performance to overcome this we use ASTC code . ASTC code are full rank, full rate and non vanishing constant minimum determinant for increasing spectral efficiency and reducing Peak to Average Power Ratio (PAPR) . Keywords— Adaptive modulation ASTC code, Capacity, BER, Ergodic capacity, PAPR, Spectral Efficiency and SNR
Analysis of Reduction of PAPR by Linear Predictive Coding in OFDM AnuragSingh1049
The major challenge in orthogonal frequency division multiplexing (OFDM) is to reduce high peak to average power ratio (PAPR) that leads to non linear distortion for the application of high power amplifier. PAPR is defined as the ratio between the maximum instantaneous power and its average power. In this paper, we have presented new PAPR reduction technique to reduce peak to average power ratio using Linear predicting coding (LPC) in OFDM system. In this paper, proposed technique show the significant reduction in PAPR without any harmful degradation in power spectral density (PSD), computational complexity (CC) and performance error of the system. This proposed method can be applied for any number of subcarrier and independent of modulation scheme under Additive White Gaussian Noise (AWGN) channel.
Performance analysis of adaptive filter channel estimated MIMO OFDM communica...IJECEIAES
Advanced Communication Systems are wideband systems to support multiple applications such as audio, video and data so and so forth. These systems require high spectral efficiency and data rates. In addition, they should provide multipath fading and inter-symbol interference (ISI) free transmission. Multiple input multiple output orthogonal frequency division multiplexing (MIMO OFDM) meets these requirements Hence, MIMOOFDM is the most preferable technique for long term evaluation advanced (LTEA). The primary objective of this paper is to control bit error rate (BER) by proper channel coding, pilot carriers, adaptive filter channel estimation schemes and space time coding (STC). A combination of any of these schemes results in better BER performance over individual schemes. System performance is analyzed for various digital modulation schemes. In this paper, adaptive filter channel estimated MIMO OFDM system is proposed by integrating channel coding, adaptive filter channel estimation, digital modulation and space time coding. From the simulation results, channel estimated 2×2 MIMO OFDM system shows superior performance over individual schemes.
Analysis of Peak to Average Power Ratio Reduction Techniques in Sfbc Ofdm SystemIOSR Journals
Abstract: Orthogonal Frequency Division Multiplexing (OFDM) has become the most popular modulation echnique for high speed data transmission. But the great disadvantage of the OFDM technique is its high Peak to Average Power Ratio (PAPR). In this paper, the Selected Mapping (SLM) technique and Clipping and Differential Scaling is applied to Space Frequency Block Coded (SFBC) OFDM systems to reduce the PAPR with Alamouti coding scheme. In SLM technique, different representations of OFDM symbols are generated by rotation of the original OFDM frame by different phase sequences, and the signal with minimum PAPR is selected and transmitted. To compensate for the effect of the phase rotation at the receiver, it is necessary to transmit the index of the selected phase sequence as side information (SI). Additionally, a suboptimum detection method that does not need SI is introduced at the receiver side. In Clipping and Differential Scaling technique, the amplitude of complex OFDM signal is clipped and then scaled in such a way so that the PAPR is reduced without causing much degradation in bit error rate (BER). The threshold values for clipping and scaling is determined using Monte Carlo Simulations. Simulation results show that the SLM method and Clipping and Scaling method effectively reduce the PAPR. Keywords: Orthogonal frequency division multiplexing (OFDM), peak to average power ratio (PAPR), selected mapping (SLM), space frequency block coded (SFBC), Side information (SI), high power amplifiers (HPA), complementary cumulative density function (CCDF), inter-symbol interference (ISI).
Design Ofdm System And Remove Nonlinear Distortion In OFDM Signal At Transmit...Rupesh Sharma
although OFDM seems to be a solution to keep up with
the demand of increasing data rates, it has some drawbacks.
Sensitivity to high PAPR is the most significant of these
drawbacks. The main objective of this paper was to investigate
and document the effects of PAPR on the performance of OFDM
based digital communications under different channel conditions.
A step-by-step approach was adopted in order to achieve the
objective of this paper. The first step is to provide a basic
background on the principles of OFDM. The reasons for the
PAPR and a theoretical analysis of these effects on OFDM
systems are documented. The OFDM system has a high peak-toaverage
power ratio (PAPR) that can cause unwanted saturation
in the power amplifiers, leading to in-band distortion and out-ofband
radiation. To be able to observe the system behavior, the
simulation results for different channel models are presented in
graphical form. Next, the simulation results obtained in this work
are compared to the simulation results reported in related studies
PAPR REDUCTION OF OFDM SIGNAL BY USING COMBINED HADAMARD AND MODIFIED MEU-LAW...IJCNCJournal
Orthogonal frequency division multiplexing (OFDM) is a technique which gives high quality of service (QOS) to the users by mitigating the fading signals as well as high data rates in multimedia services. However, the peak-to-average power ratio (PAPR) is a technical challenge that reduces the efficiency of RF power amplifiers. In this paper, we propose the combined Hadamard transform and modified meu-law companding transform method in order to lessen the effects of the peak-to-average power ratio of the
OFDM signal. Simulation results show that the proposed scheme reduces PAPR compared to other companding techniques as well as the Hadamard transform technique when used on its own.
Performance Analysis of PAPR Reduction in MIMO-OFDMIJARBEST JOURNAL
Authors: Jayaraman.G1, VeeraKumar K2, Selvakani.S3
Abstract— In communication system, it is aimed to provide highest possible
transmission rate at the lowest possible power and with the least possible noise. MIMOOFDM
has been chosen for high data rate communications and widely deployed in many
wireless communication standards. The major drawback in OFDM signal transmission is
high PAPR. In previous, use clipping technique to tackle this problem. In this paper, use
EM-GAMP algorithm to reduce PAPR in considerable amount.
Channel Equalization of WCDMA Downlink System Using Finite Length MMSE-DFEIOSR Journals
Abstract: The performance of WCDMA system deteriorates in the presence of multipath fading environment. Fading destroys the orthogonality and is responsible for multiple access interference (MAI). Though conventional rake receiver provides reasonable performance in the WCDMA downlink system due to path diversity, but it does not restores the orthogonality. Linear equalizer restores orthogonality and suppresses MAI, but it is not efficient, since its performance depends on the spectral characteristics of the channel. To overcome this, Minimum Mean Square Error- Decision Feedback Equalizer (MMSE-DFE) with a linear, anticausal feedforward filter, causal feedback filter and simple detector is proposed in this paper. The filter taps of finite length DFE is derived using the cholesky factorization theory, capable of suppressing noise, Intersymbol Interference (ISI) and MAI. This paper describes the WCDMA downlink system using finite length MMSE-DFE and takes into consideration the effects of interference which includes additive white gaussian noise, multipath fading, ISI and MAI. Furthermore, the performance is compared with conventional rake receiver and MMSE and the simulation results are shown. Keywords – MMSE, MMSE-DFE, rake receiver, WCDMA
Channel Equalization of WCDMA Downlink System Using Finite Length MMSE-DFEIOSR Journals
The performance of WCDMA system deteriorates in the presence of multipath fading environment.
Fading destroys the orthogonality and is responsible for multiple access interference (MAI). Though
conventional rake receiver provides reasonable performance in the WCDMA downlink system due to path
diversity, but it does not restores the orthogonality. Linear equalizer restores orthogonality and suppresses
MAI, but it is not efficient, since its performance depends on the spectral characteristics of the channel. To
overcome this, Minimum Mean Square Error- Decision Feedback Equalizer (MMSE-DFE) with a linear,
anticausal feedforward filter, causal feedback filter and simple detector is proposed in this paper. The filter taps
of finite length DFE is derived using the cholesky factorization theory, capable of suppressing noise,
Intersymbol Interference (ISI) and MAI. This paper describes the WCDMA downlink system using finite length
MMSE-DFE and takes into consideration the effects of interference which includes additive white gaussian
noise, multipath fading, ISI and MAI. Furthermore, the performance is compared with conventional rake
receiver and MMSE and the simulation results are shown.
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.
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.
A low complexity partial transmit sequence scheme for better papr reduction i...eSAT Journals
Abstract The main drawback of OFDM system is the high Peak to Average Power Ratio (PAPR) of the transmitted signals. Partial transmit sequence scheme is a promising algorithm to reduce the peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM). The Partial Transmit Sequence (PTS) consist of several inverse fast Fourier transform (IFFT) operations and complicated calculations to obtain optimum phase sequence which results in increasing the computational complexity of PTS. A phase sequence applied to the PTS Scheme reduces its complexity but at the expense of slight degradation in PAPR reduction. In this paper, for further reduction of PAPR the peak clipping of the OFDM signal is introduced along with the PTS with new phase sequence scheme. Since clipping is one of the simplest techniques of PAPR reduction, it does not increase the complexity of the system much and a better PAPR reduction is obtained with the combined effect of clipping and PTS with New Phase Sequence. But the clipping technique introduce some distortion in the signal, however peak clipping of signal below a particular threshold can maintain the BER in the tolerable range. The clipping threshold selected will be different for different OFDM systems. Index Terms: OFDM, Peak to Average Power Ratio (PAPR), Partial Transmit Sequence (PTS), Clipping.
CS Based Channel Estimation for OFDM Systems under Long Delay Channels Using ...IJERA Editor
Orthogonal frequency division multiplexing (OFDM) is a technique which are used in the next-generation wireless communication. Channel estimation in the OFDM technique is one of the big challenges, ever since high-resolution channel estimation can significantly improve the equalization at the receiver and consequently enhance the communication performances. Channel computation using superimposed pilot sequences is also a fully new area, idea for using superimposed pilot sequences has been proposed by various authors for different applications. In this paper, we are introduced a high accurate, low complexity compressive sensing (CS) based channel estimation namely Auxiliary information based Subspace Pursuit (ASP) in TFT-OFDM systems. ASP based channel estimation in TFT-OFDM system is based on two steps. First is, by exploiting the signal structure of recently proposed TDM-OFDM scheme, the supporting channel information is obtained. Second is, we propose the supporting information based subspace pursuit (SP) algorithm to use a very small amount of frequency domain pilots embedded in the OFDM block used for the exact channel estimation. Moreover, the obtained auxiliary channel information is adopted to reduce the complexity of the conventional SP algorithm. Simulation results demonstrate a important reduction of the number of pilots relative to least-squares channel estimation and supporting high-order modulations like 256 QAM.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
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.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
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.
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Reduction of PAPR and Efficient detection ordering scheme for MIMO Transmission Systems Using Power Control
1. V.Sreevani Int. Journal of Engineering Research and Applications www.ijera.com
ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 1) December 2015, pp.31-35
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Reduction of PAPR and Efficient detection ordering scheme for
MIMO Transmission Systems Using Power Control
V.Sreevani1
, K.Suma2
Department of Electronics and communications Engineering. G.I.E.T
Department of Digital Electronics Engineering, G.I.E.T
Abstract
The technical challenges for communication engineers is the development of best performance wireless
networks with negligible amount of distortions. We have to consider multipath propagation attenuation and
radio spectrum inefficiency. Now a days, In MIMO (Multi Input Multi Output) systems there is a huge demand
for the networks with the high transmission rates and better quality of service which are having low PAPR ratio.
Instead of OFDMA, filter banks are used in massive MIMO to reduce the complexity. But they are error prone
to noise. This base paper discusses about PAPR reduction in MIMO systems using different precoding based
OFDM systems. Mainly, minimization of multi-antenna systems by controlling the transmission power and
reduction of PAPR using ZC (Zadoff-Chu) matrix transform.
Keywords: OFDM, Peak-to-average power ratio
I. Introduction
Filter banks used in massive MIMO to reduce
the complexity are error prone to noise [1].MIMO
can be implemented efficiently using OFDM [2].
Due to the robustness against narrowband
interference, good spectral efficiency, improved
sevice quality and frequency selective fading, OFDM
became the technology of choice in wired and
wireless digital communication systems for the next
generation [4]. OFDM stands for Orthogonal
Frequency Division Multiplexing. It is a multicarrier
transmission scheme. By using a Cyclic Prefix (CP),
a Guard interval (GI) is inserted so that OFDM can
withstand to Inter symbol interference. Using a
simple equalizer OFDM moderates the frequency
selectivity of the multipath channel [5]. Asymmetric
digital subscriber line (ADSL) uses OFDM
technology. In various communication standards like
DVB (Digital Video Broadcasting), DAD (Digital
Audio Broadcasting) and even in the networks
beyond 3G
The biggest disadvantage in Orthogonal
Frequency Division Multiplexed signal is the peak-
to-average power ratio[3]. In the literature many
number of reduction techniques for PAPR have been
proposed. [7]- [12]. However, precoding techniques
are simple linear techniqus because they does not
require any additional information. This paper
consists the presentatation of a PAPR reduction using
the ZCT-ROFDM (Zadoff-Chumatrix Transform
Row-wise precoder based OFDM) system with
RRC(Root Raised Cosine) pulse shaping and
comparision with other precoding based OFDM
systems. The efficient detection ordering scheme for
multi input- multi output transmission systems using
power control is proposed and verified using Matlab
and the results are analyzed.
The remaining portions of this paper are
categorized as follows: the description of section II is
basics of OFDM, PAR or PAPR, and ZCT method.
System model, ZCT precoded OFDM (ZCT-OFDM)
system[11] and ordering scheme are presented in
section III and simulation results are presented in
section IV and conclusion of the paper is presented in
section V.
II. OFDM & ZCT
Because of their great potential of enhancing the
system’s performance, the utilization of MIMO
(multiple-input multiple-output) systems became an
active area of research as well as practical transceiver
implementations for.
Fig 1: A conventional OFDM system
The block diagram of conventional OFDM
system is showned in fig (1).The input to the serial to
parallel converter is the baseband modulated symbols
from mapper. It generates a complex vector of size
N.It is written as X=[X0,X1,X2,.......XN-1]T
.Then it is
passed through IFFFT block to generate complex
RESEARCH ARTICLE OPEN ACCESS
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ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 1) December 2015, pp.31-35
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baseband OFDM signal which has N subcarriers.It is
given by
Xn =
1
√𝑁
𝑋𝑁−1
𝑘=0 k. 𝑒 𝑗2𝜋
𝑛
𝑁
𝑘
… …. Eq(1)
Where n=0,1,2…..N-1
The PAPR for the above system can be defined as
follows
PAPR =
max [ 𝑥 𝑛
2]
𝐸[ 𝑥 𝑛
2]
Eq-(2)
Where E [.] indicates the expectation.
It helps in band radiation.
By filling ZCT kernel row-wise or alternatively
column wise, the ZCTs are obtained from
ZC(Zadoff-Chu) sequences . Column wise filling
give rise 7.8 dB at clip rate of 10-3 while Row-wise
filling gives rise to CE-OFDM (Constant Envelope
OFDM ) system with 0 dB PAPR, with system
subcarriers for QPSK modulation or any modulation
depending upon the type of communication.
Constant Envelope OFDM (orthogonal
frequency division multiplexing) systems helps to
keep in band radiation with the help of pulse shaping
and the PAPR are not a constant zero db .In this
paper we show PAPR analysis of several pre-coding
based OFDM techniques with the popular Rout
Raised Cosine(RRC) pulse shaping. The simulation
results shows that ZCT row wise pre-coder
OFDM(ZCT-R-OFDM) system has lowered PAPR
then the ZCT Column-wise pre-coder based OFDM
(ZCT-C-OFDM)system, the hardward transform pre-
coder based OFDM (WHT-OFDM) systems and the
conventional OFDM systems.
We can derive the ordering of the system from
the convexity of the function. From the ordering of
the system we can get converge to the geometric
mean. The use of the geometric mean is to maintain
the constant threshold, and also ordering of the
algorithm is derived from the geometric mean. For
this modified scheme of employing adaptive
threshold technique is developed by correlation
among the ordering result. The simultaneous results
are obtained by the theoretical analysis. QR-
decomposition not only require reduced
computational complexity when we compared to the
conventional scheme. Due to this error performance
is improved in result.
III. SYSTEM MODEL
A.ZC Sequences and ZCT (Zadoff-chu Matrix
Transform)
ZC (Zadoff-Chu) sequences have optimum
correlation properties. They are class of poly phase
sequences. ZC sequences have constant magnitude
and an ideal periodic auto-correlation. According to
[13], ZC sequences of length N can be defined as
an =
𝑒
𝑗2𝜋𝑟
𝑁
𝑘(𝑘+1)
2
+𝑞𝑘 𝑓𝑜𝑟 𝑁 𝑂𝑑𝑑
𝑒
𝑗2𝜋𝑟
𝑁
k2
2
+𝑞𝑘
𝑓𝑜𝑟 𝑁 𝐸𝑣𝑒𝑛
…3
where k = 0, 1, 2… N-1, q is any integer, r is any
integer relatively prime to N and j=√-1.
The kernel of the ZCT is defined in eqn(4),is
obtained by reshaping the ZC sequence by k=mL+l
as hereunder.
A=
𝑎00 𝑎01. . . 𝑎0𝐿−1
𝑎10.....
𝑎11. . . 𝑎1𝐿−1....
𝑎(𝐿−1)0 𝑎(𝐿−1)1. . 𝑎(𝐿−1)(𝐿−1)
...4
Here l is the column variable and m is the
row variable.In other words N=L2
point long ZC
sequence fills the kernel of the matrix rowwise.In this
case PAPR reduces to 0dB[10].However the PAPR
reduces to 7.8dB,it does not reduces to 0dB,if the
kernel is filled columnwise[7].
B.OFDM system with ZCT precoding:
ZCT precoded OFDM system is showned in
fig(2).Here,The ZCT kernel acts as a rowwise
precoding matrix of A of dimensions N=L×L and it
is applied to each symbol to reduce PAPR.The
baseband modulated data is passed through S/P
converter in the ZCT precoded OFDM system which
generates a complex vector of size L. The complex
vector can be written as
X= [X0, X1, …XL-1]T
.
Fig 2: A ZCT precoded OFDM System
After that Zadoff Chu matrix transform precoding is
applied to complex vector X.This precoding
technique transforms the complex vector into a new
vector with same length L.The new vector obtained
by ZCT precoding with lenth L can be written as
Y=AX=[Y0,Y1,Y2,.......YL-1]T
Where A is a precoder matrix of size L× 𝐿
and 𝑦 𝑚 can be written as
𝑌𝑚 = 𝑎 𝑚,𝑙. 𝑋𝑙
𝐿−1
𝑙=0 , 𝑚 = 0,1, . . 𝐿 − 1 ......(5)
Here 𝑎 𝑚,𝑙 indicates mth
row and lth
column.
The ZCT-R-OFDM complex baseband signal with L
subcarriers is defined as
𝑥 𝑛 =
1
√𝐿
𝑌𝑚 . 𝑒 𝑗2𝜋
𝑛
𝐿
𝑚𝐿−1
𝑚=0 , .................(6)
where 𝑛 = 0,1, . . . . . 𝐿-1
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ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 1) December 2015, pp.31-35
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After RRC(Root Raised Cosine)pulse shaping and
D/A of n Samples ,the complex passband transmit
signal x(t) of ZCT-R-OFDM can be written as
x(t)=𝑒 𝑗 𝑤 𝑐 𝑡
𝑥 𝑛
𝐿−1
𝑛=0 . 𝑟(𝑡 − 𝑛𝑇) ......(7)
Here 𝜔𝑐 is the carrier frequency,r(t) is the baseband
pulse and 𝑇=after IFFT ,compressed symbol duration
in seconds.
The definition of Root Raised Cosine filter is
r(t) =
sin (
𝜋𝑡
𝑇
(1−𝛼))+4𝛼
𝑡
𝑇
cos (
𝜋𝑡
𝑇
(1+𝛼))
𝜋𝑡
𝑇
(1−
16𝛼2 𝑡2
𝑇2 )
....(8)
With pulse shaping the PAPR of the ZCT-R-OFDM
is defined as
PAPR=
max 0≤𝑡≤𝑁𝑇 [ 𝑥(𝑡) 2]
1
𝑁𝑇
[ 𝑥(𝑡) 2]
𝑁𝑇
0 𝑑𝑡
.........(9)
without pulse shaping PAPR of ZCT-R-OFDM can
be defined as
PAPR=
max 𝑛=0,1...,𝑁−1[ 𝑥 𝑛
2]
1
𝑀
[ 𝑥 𝑛
2]𝑁−1
𝑛=0
......(10)
Assume that the number of transmit antennas
is𝑁𝑡 and the number of receiving antennas is 𝑁𝑟 in
MIMO system. The 𝑁𝑟 𝑋𝑁 𝑇 matrix H with the
element 𝑗𝑖 represents flat-fading MIMO channel.
𝑗𝑖 representsthe channel gain from ith
transmit
antenna to jth
receive antenna. The 𝑁𝑟 𝑋1 signal
vector received 𝑌 = [𝑦1, … , 𝑦 𝑁𝑟 ] 𝑇
is written
as
y =
𝐸 𝑠
𝑁𝑡
HPx + n ----- (11)
Where X = [ x1 … , xNr ]T
denotes NtX1 the
transmittedsignal vector, and n = [n1, … . , nNr
]T
is
the one–dimensional noise vector. In noise vector the
elements follow complex zero mean Gaussian
distribution with variance of σn
2
. Es is the total
transmitted signal energy on transmit antennas and P
= Nt ,diag(P1,P2,,….P Nt )
denotes the diagonal PA precoding matrix.
An(Nr+Nt)X Ntaugmented channel matrix H
,(Nr +Nt)X 1 an extended receive vector y andNtX 1
an zero matrix0Nt,1
,to express the signal model for
the MMSE-QR detector, is given by.
𝐻 =
𝐻
𝜍𝑛 𝐼 𝑁𝑡
𝑜𝑟𝑑𝑒𝑟𝑖𝑛𝑔 𝑄 𝑅 𝑎𝑛𝑑 𝑦 =
𝑦
0 𝑁𝑡,1
--
(12)
Fig 3: MIMO Transmission model with QR OSIC
and ZCT Decoder
The detection-order defines the upper
triangular matrix𝑅 differently which determines the
post detection SINR 𝜌 𝑘 and SNR of the data stream is
given as
𝜌 𝑘 =
𝐸 𝑠
𝜍 𝑛
2 𝑃𝑘
2
𝑅 𝑘,𝑘
2
− 1 , k= 1,2,…..,Nt ....(13)
Using the architecture shown in Fig.3 ,The
BER-minimized PA transmission using QR-
decomposition based ZCT-OSIC detection can be
performed. Transmission power Pk is assigned to
each data stream based on the feedback information
of the diagonal elements𝑅 𝑘,𝑘.Through a diagonal PA
matrix, the independently encoded symbols are
processed and then they are transmitted from Nt data
streams. According to the designated detection-order,
The QR-OSIC receiver detects the transmit symbols
sequentially.
TABLE 1:
Proposed Detection Ordering Algorithm
Step Operation for each step
1. 𝑅 ≡ 0 𝑁𝑡
, 𝑄 ≡ 𝐻 ,k={1,2,3….𝑁𝑡 ), 𝜇1 = 𝜇
2. For i=1,2,3…𝑁𝑡
3. 𝜏𝑖 = 𝑄: ,𝑖
2
4. End
5. For l=1,2,3…𝑁𝑡
6. 𝐾𝑙 = arg 𝑚𝑖𝑛
𝜔
𝜏 𝜔 − 𝜇𝑙
7. Fixed : 𝜇𝑙+1 = 𝜇𝑙 , Adaptive:
𝜇𝑙+1=
𝜇 𝑙
𝑅𝑙,𝑙
𝑁 𝑡−𝑙+1
𝑁 𝑡−𝑙+1
𝑁 𝑡−𝑙
8. 𝑅(:,𝑙) 𝑅(:,𝑘 𝑡), 𝜏𝑙 𝜏 𝑘,𝑙
K(l) k( 𝑘𝑙 ), 𝑄 1:𝑁 𝑟−𝑙+1,𝑡
𝑄 1:𝑁 𝑟−𝑙+1,𝑘 𝑙
9. 𝑅(𝑙,𝑙)= 𝜏𝑙
10. 𝑄(:,𝑙) =
𝑄 :,𝑙
𝑅 𝑙,𝑙
11 For m= l+1,…..𝑁𝑡
12. 𝑅 𝑙,𝑚 = 𝑄(:,𝑙)
𝐻
. 𝑄 :,𝑚
13. 𝑄 :,𝑚 = 𝑄 :,𝑚 − 𝑅 𝑙,𝑚 . 𝑄 :,𝑙
14. 𝜏 𝑚 = 𝜏 𝑚 − 𝑅(𝑙,𝑚)
2
15. End
16. End
IV. Simulation Results
In order to show the simulation results for PAPR
analysis using ZCT-R-OFDM with RRC pulse
shaping,input is randomly generated and then
modulated by Quadrature phase shift
keying(QPSK).All the simulation results are
performed based on 105
random OFDM blocks.
parameters of system:
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ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 1) December 2015, pp.31-35
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1. system subcarriers:64,512
2. precoding techniques:WHT,ZCT
3. modulation technique:QPSK
4. Pulse shaping:RRC
5. Rolloff factor 𝛼 for RRC:𝛼 = 0.22
6. Oversampling factor=4
PAPR is evaluated stastically using
complementary cumulative distributive function.The
probability of PAPR exceeding the given threshold is
CCDF=Prob(PAPR>PAPRO)
Result of ZCT over other conventional PAPR
techniques with N=64,512 with alpha 0.2
It is clear from the simulation results that the PAPR
value of ZCT-R-OFDM is less when compared to
other PAPR techniques even when the N value is
increased/Decreased.
V. CONCLUSION
In this paper, we present a PAPR reduction using
the ZCT-R-OFDM system for MIMO transmission
with Root raised cosine pulse shaping. From the
results and series of experiments conducted, we
conclude that ZCT proves to be a better model among
the other pre-coding techniques like WHT etc. in
terms of PAPR. Another noticable fact is that, pulse
shaping increases the PAPR of the ZCT-R-OFDM
from 0dB to 5dB. Any power increase and complex
optimization is not required in ZCT-R-OFDM system
and no need to send any additional information to the
receiver. In addition, this system offer substantial
performance gain in fading multipath channels.It is
sufficient to confirm the superiority of the proposed
design because the ordering algorithm of previous
studies comply with the stategy of the B-OSIC
(Ordered Successive Inerference Cancellation) [14]-
[16].It also take advantage of the frequency
variations of the communication channel and
Performing ZCT-QR decomposition based OSIC
detection made it more eligible for transmission.
REFERENCES
[1] Arman Farhang*, 'Nichola Marchetti*,
Linda E.Dolye and Farhang Boroujeny,'
Filter bank Multicarrier for Massive MIMO',
feb 2014
[2] Hong-Jie Chou, “PAPR Reduction
Techniques with Hybrid SLM-PTS Schemes
for OFDM Systems.” IEEE Trans.
Consumer Electronics, vol.1,978-990,Dec
2012.
[3] J.Hoydis, S. Ten Brick and M. Debbah,'
Massive MIMO in the UL/DL of cellular
networks: How many antennas do we need',
IEEE journal on selected areas of
communications, vol31, no.2.pp.160-171,
2013
[4] Y. Wu and Z. Y. William, “Orthogonal
frequency division multiplexing: A multi-
carrier modulation scheme,” IEEE Trans.
Consumer Electronics, vol. 41, no. 3, pp.
392–399, Aug. 1995.
[5] B. Muquet, Z. Wang, G. B. Giannakis, M.
Courville, and P. Duhamel, “Cyclic
prefixing or zero padding for wireless
multicarriertransmissions,'' IEEE Trans.
Comm., vol. 50, pp. 2136-2148, Dec.2002.
[6] R. V Nee and A. Wild, “Reducing the Peak-
To-Average Power Ratioof OFDM,” 48th
IEEE Vehicular Technology Conference,
VTC98, vol.3, 18-21 May 1998.
[7] Y. Kuan Min and V. Jeoti, “A Novel Signal
Independent Techniquefor PAPR Reduction
in OFDM Systems", International
Conference onSignal processing,
communication and networking (IEEE-
ICSCN2007), 22-24 Feb. 2007.
[8] I. Baig and V. Jeoti, “PAPR Analysis of
DHT-Precoded OFDM System for M-
QAM”, the 3rd International Conference on
Intelligentand Advanced Systems
(ICIAS2010), June 2010.
[9] Y. Tasi, G. Zhang, and X. Wang,
“Orthogonal Polyphase Codes forConstant
Envelope OFDM-CDMA System,” IEEE,
WCNC, pp. 1396– 1401, 3-6 April 2006.
5. V.Sreevani Int. Journal of Engineering Research and Applications www.ijera.com
ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 1) December 2015, pp.31-35
www.ijera.com 35|P a g e
[10] S. C. Thompson, A. U. Ahmed, J. G.
Proakis, J. R. Zeidler, and M. J.Geile,
“Constant envelope OFDM,'' IEEE Trans.
Communications,vol. 56, pp. 1300-1312,
Aug. 2008.
[11] I. Baig and V. Jeoti,” PAPR Reduction in
OFDM Systems: Zadoff-Chu Matrix
Transform Based Pre/Post-Coding
echniques”, 2nd
International Conference on
Computational IntelligenceCommunication
Systems and Networks (CICSyN 2010), 28-
30 July2010.
[12] V. Jeoti and I. Baig, “A Novel Zadoff-Chu
Precoder Based SLM Technique for PAPR
Reduction in OFDM Systems”, invited
paper, Proceedings of 2009 IEEE
International Conference on Antennas,
Propagation and Systems (INAS 2009), 3-5
Dec. 2009.
[13] I. Baig and V. Jeoti, “DCT Precoded SLM
Technique for PAPR
[14] J.Benesety, Y.Huang, and J.Chen, "A fast
recursive algorithm for optimum sequential
signal detection in a BLAST system", IEEE
Trans. signal process, vol.51.no.7.pp.1722-
1730, july 2003
[15] Z.Yan, K.V.Wong, and Z.Q.Luo, "Optimal
diagonal precoder for multiantenna
communication systems", IEEE Trans.
signal process, vol.53.no.6.pp.180-187, jan.
2007
[16] N. Wang, S.D. Blostein, "Approximate
minimum BER power allocation for MIMO
spatial multiplexing systems". IEEE
Trans.column,vol55,no.1,pp.180-187,jan
2007