1) Adaptive array antennas in cognitive relay networks are proposed to improve system performance by reducing symbol error rate. Wiener solution and least mean square algorithms are explored to calculate optimal antenna weights.
2) Simulations show that placing adaptive array antennas at the source node provides better performance than at the relay or destination nodes. Additional enhancements include increasing the source gain, decreasing the relay gain, and using more antenna elements.
3) Under different channel conditions, adaptive array antennas perform best under additive white Gaussian noise and improve under Rayleigh fading by increasing the step size or number of iterations in the least mean square algorithm.
performance analysis of MUSIC and ESPRIT DOA estimation used in adaptive arra...CSCJournals
MUSIC and ESPRIT DOA Estimaion algorithms are widely used in adaptive array to locate the desired desired signal.MUSIC is found to be more stable and accurate and widely used inthe design of adaptive array.
BER Analysis ofImpulse Noise inOFDM System Using LMS,NLMS&RLSiosrjce
IOSR Journal of Computer Engineering (IOSR-JCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of computer engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in computer technology. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This document summarizes a research paper that analyzes the performance of adaptive equalization algorithms RLS and CMA for noisy speech signals. It finds that the RLS algorithm has a faster convergence rate but requires more computing power, while the CMA algorithm has a slower convergence rate but requires less computing power and performs relatively better. The parameters of an adaptive equalizer combining these algorithms with a noisy audio source are optimized in simulations. The results show that CMA has a better frequency response and MSE convergence than RLS in the presence of noisy audio. Therefore, blind equalization using CMA is concluded to perform better than trained equalization with RLS for noisy speech signals.
Adaptive Channel Equalization for Nonlinear Channels using Signed Regressor F...IDES Editor
Wireless communication systems are affected by
inter-symbol interference (ISI), co-channel interference in
the presence of additive white Gaussian noise. ISI is primarily
due to the distortion caused by frequency and time selectivity
of the fading channel and it causes performance degradation.
Equalization techniques are used to mitigate the effect of ISI
and noise for better demodulation. This paper presents a novel
technique for channel equalization. Here a Signed Regressor
adaptive algorithm based on FLANN (Functional Link Artificial
Neural Network) has been developed for nonlinear channel
equalization along with the analysis of MSE and BER. The
results are compared with the conventional adaptive LMS
algorithm based FLANN model. The Signed Regressor FLANN
shows better performance as compared to LMS based FLANN.
The equalizer presented shows considerable performance
compared to the other adaptive structure for both the linear
and non-linear models in terms of convergence rate, MSE
and BER over a wide range.
Hybrid protocol for wireless EH network over weibull fading channel: performa...IJECEIAES
In this paper, the hybrid TSR-PSR protocol for wireless energy harvesting (EH) relaying network over the Weibull fading channel is investigated. The system network is working in half-duplex (HD) mode. For evaluating the system performance, the closed-form and integral-form expressions of the outage probability (OP) are investigated and derived. After that, numerical results convinced that our derived analytical results are the same with the simulation results by using Monte Carlo simulation. This paper provides a novel recommendation for the wireless EH relaying network.
An Energy-Efficient Dual Hop Cooperative Relay Model With Best Relay Selectioninventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
IRJET- Chord Classification of an Audio Signal using Artificial Neural NetworkIRJET Journal
This document presents a method for classifying chords in an audio signal using an artificial neural network. It extracts Chroma DCT-Reduced Log Pitch (CRP) features from a dataset of 2,000 recordings of 10 guitar chords. These CRP features are used to train a two-layer feedforward neural network with scaled conjugate gradient backpropagation. The trained network is able to classify chords in the input audio with an overall accuracy of 89.3%. The method demonstrates effective chord classification using a machine learning approach with chroma-based audio features.
performance analysis of MUSIC and ESPRIT DOA estimation used in adaptive arra...CSCJournals
MUSIC and ESPRIT DOA Estimaion algorithms are widely used in adaptive array to locate the desired desired signal.MUSIC is found to be more stable and accurate and widely used inthe design of adaptive array.
BER Analysis ofImpulse Noise inOFDM System Using LMS,NLMS&RLSiosrjce
IOSR Journal of Computer Engineering (IOSR-JCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of computer engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in computer technology. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This document summarizes a research paper that analyzes the performance of adaptive equalization algorithms RLS and CMA for noisy speech signals. It finds that the RLS algorithm has a faster convergence rate but requires more computing power, while the CMA algorithm has a slower convergence rate but requires less computing power and performs relatively better. The parameters of an adaptive equalizer combining these algorithms with a noisy audio source are optimized in simulations. The results show that CMA has a better frequency response and MSE convergence than RLS in the presence of noisy audio. Therefore, blind equalization using CMA is concluded to perform better than trained equalization with RLS for noisy speech signals.
Adaptive Channel Equalization for Nonlinear Channels using Signed Regressor F...IDES Editor
Wireless communication systems are affected by
inter-symbol interference (ISI), co-channel interference in
the presence of additive white Gaussian noise. ISI is primarily
due to the distortion caused by frequency and time selectivity
of the fading channel and it causes performance degradation.
Equalization techniques are used to mitigate the effect of ISI
and noise for better demodulation. This paper presents a novel
technique for channel equalization. Here a Signed Regressor
adaptive algorithm based on FLANN (Functional Link Artificial
Neural Network) has been developed for nonlinear channel
equalization along with the analysis of MSE and BER. The
results are compared with the conventional adaptive LMS
algorithm based FLANN model. The Signed Regressor FLANN
shows better performance as compared to LMS based FLANN.
The equalizer presented shows considerable performance
compared to the other adaptive structure for both the linear
and non-linear models in terms of convergence rate, MSE
and BER over a wide range.
Hybrid protocol for wireless EH network over weibull fading channel: performa...IJECEIAES
In this paper, the hybrid TSR-PSR protocol for wireless energy harvesting (EH) relaying network over the Weibull fading channel is investigated. The system network is working in half-duplex (HD) mode. For evaluating the system performance, the closed-form and integral-form expressions of the outage probability (OP) are investigated and derived. After that, numerical results convinced that our derived analytical results are the same with the simulation results by using Monte Carlo simulation. This paper provides a novel recommendation for the wireless EH relaying network.
An Energy-Efficient Dual Hop Cooperative Relay Model With Best Relay Selectioninventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
IRJET- Chord Classification of an Audio Signal using Artificial Neural NetworkIRJET Journal
This document presents a method for classifying chords in an audio signal using an artificial neural network. It extracts Chroma DCT-Reduced Log Pitch (CRP) features from a dataset of 2,000 recordings of 10 guitar chords. These CRP features are used to train a two-layer feedforward neural network with scaled conjugate gradient backpropagation. The trained network is able to classify chords in the input audio with an overall accuracy of 89.3%. The method demonstrates effective chord classification using a machine learning approach with chroma-based audio features.
Improved Ad-Hoc Networks Using Cooperative DiversityIJCSIT Journal
In this paper an ad-hoc network having source, a
destination and a third station which is a relay is analyzed.
The channels used here are modeled having thermal noise,
Rayleigh fading and path loss. Different methods for
combining and diversity protocols are compared.
Heuristic based adaptive step size clms algorithms for smart antennascsandit
This document summarizes research on heuristic-based adaptive step size complex least mean square (CLMS) algorithms for smart antennas. It presents Benveniste and Mathews algorithms, which use heuristics with CLMS to speed up convergence. Simulations show these algorithms outperform CLMS and augmented CLMS in convergence rate while achieving similar performance in terms of half power beamwidth and side lobe level of the array factor. The key advantage of these algorithms is faster convergence for the output signal of smart antenna systems compared to baseline algorithms like CLMS.
This document proposes and evaluates a new chaotic communication system called Correlation Delay Shift Keying (CDSK). It summarizes the characteristics and advantages of using chaotic signals for communication. It then describes the CDSK system and compares its bit error rate performance using two different chaos maps (Tent map and a newly proposed Boss map) in additive white Gaussian noise and Rayleigh fading channels. The results show that the Boss map provides better bit error rate performance than the Tent map.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
PERFORMANCE EVALUATION OF BER FOR AWGN, AWGN MULTIPATH AND RAYLEIGH FADING CH...IJEEE
This document evaluates the performance of bit error rate (BER) for different digital modulation techniques over additive white Gaussian noise (AWGN), AWGN multipath, and Rayleigh fading channels. It presents simulation results comparing the BER of binary phase-shift keying (BPSK) and quadrature phase-shift keying (QPSK) modulation under varying signal-to-noise ratio (SNR) levels for AWGN and AWGN multipath channels, and under varying Doppler shift levels for Rayleigh fading channels. The results show that BPSK has better BER performance than QPSK, and that BER is lowest for AWGN channels and highest for Rayleigh fading channels.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
Telecommunication System Engineering NotesHaris Hassan
Telecommunications engineering, or telecoms engineering, is an engineering discipline centered on electrical and computer engineering which seeks to support and enhance telecommunication systems.
Physical security with power beacon assisted in half-duplex relaying networks...TELKOMNIKA JOURNAL
In this research, we proposed and investigated physical security with power beacon assisted in half-duplex relaying networks over a Rayleigh fading channel. In this model, the source (S) node communicates with the destination (D) node via the helping of the intermediate relay (R) node. The D and R nodes harvest energy from the power beacon (PB) node in the presence of a passive eavesdropper (E) node. Then we derived the integral form of the system outage probability (OP) and closed form of the intercept probability (IP). The correctness of the analytical of the OP and IP is verified by the Monte Carlo simulation. The influence of the main system parameters on the OP and IP also is investigated. The research results indicated that the analytical results are the same as the simulation ones.
Mitigating Interference to GPS Operation Using Variable Forgetting Factor Bas...IJCNCJournal
In this paper, an interference method based on signal processing is proposed. The approach is based on
utilizing the maximum likelihood properties of the received signal. The approach is built on maximizing the
probability of the desired data. The GPS data, which is constructed using Binary Phase Shift Keying
(BPSK) modulation, is transmitted as “1’s” and as “0’s.” carried on 1575.42MHz carrier called the L1
frequency. The statistics of the GPS data and interference are utilized in terms of their distribution and
variance. The statistics are used to update (adaptively) the forgetting factor (Lambda) of the Recursive
Least Squares (RLS) filter. The proposed method is called Maximum Likelihood Variable Forgetting Factor
(ML VFF). The adaptive update takes on assigning lambda to the maximum of the probabilities of the
symbols based on the statistics mentioned.
This document analyzes and compares the performance of different adaptive beamforming techniques for smart antennas. It describes switched beamforming, which uses fixed beams, and adaptive beamforming techniques that use algorithms like LMS, SMI, RLS, CGA, CMA, and LSCMA to form an adaptive beam. It simulates these algorithms using MATLAB for a uniform linear array and compares their ability to direct the main beam towards the desired user while nulling interference. The LMS, SMI, RLS, CMA and LSCMA algorithms are found to perform well at directing the beam to the desired user, with LMS having good interference rejection and RLS providing the fastest convergence but highest computational cost.
Discrete wavelet transform-based RI adaptive algorithm for system identificationIJECEIAES
In this paper, we propose a new adaptive filtering algorithm for system identifica- tion. The algorithm is based on the recursive inverse (RI) adaptive algorithm which suffers from low convergence rates in some applications; i.e., the eigenvalue spread of the autocorrelation matrix is relatively high. The proposed algorithm applies discrete-wavelet transform (DWT) to the input signal which, in turn, helps to overcome the low convergence rate of the RI algorithm with relatively small step-size(s). Different scenarios has been investigated in different noise environments in system identification setting. Experiments demonstrate the advantages of the proposed DWT recursive inverse (DWT-RI) filter in terms of convergence rate and mean-square-error (MSE) compared to the RI, discrete cosine transform LMS (DCT-LMS), discretewavelet transform LMS (DWT-LMS) and recursive-least-squares (RLS) algorithms under same conditions.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Application of smart antenna interference suppression techniques in tdscdmamarwaeng
This document discusses the application of smart antenna interference suppression techniques in TD-SCDMA systems. It first provides background on TD-SCDMA and smart antenna technology. It then describes two adaptive beamforming algorithms - LMS and RLS - and simulates their performance at interference suppression in MATLAB. The simulation results show that both algorithms can effectively form a main beam towards the desired user and nulls towards interferers. RLS converges faster than LMS, though it has higher computational complexity. The study demonstrates that smart antenna techniques can improve signal quality in TD-SCDMA systems by suppressing interference.
DIGITAL WAVE FORMULATION OF THE PEEC METHODPiero Belforte
This document presents a digital wave formulation (DWF) method for solving the quasi-static partial element equivalent circuit (PEEC) method in the time domain. The standard PEEC model is transformed into a wave digital network by using wave variables and defining wave digital circuit elements corresponding to inductors, capacitors, resistors, sources, and connections. This allows the PEEC model to be solved as a wave digital network using a digital wave simulator (DWS). A numerical example compares the proposed DWF-PEEC solver to a standard SPICE solver, showing the DWF-PEEC method provides accurate results with significant speed-up in computation time.
PERFORMANCE EVALUATION OF ADAPTIVE ARRAY ANTENNAS IN COGNITIVE RELAY NETWORK csijjournal
Adaptive Array Antennas (AAAs) are expected to play a key role in meeting the demands of the wireless communication systems of the future. AAAs in cognitive relay network is proposed to reduce the symbol error rate and improve the system performance. Many algorithms such as wiener solution and least mean square (LMS) will be explained to show how AAAs in cognitive relay network achieves this object. AAAs at different locations will be investigated under AWGN and Rayleigh fading channel. Moreover, enhancement the system performance by showing the effect of increasing the number of AAAs element at the relay node, increasing the source gain and decreasing the relay gain. In addition, increasing the rate adaptation and number of iterations in LMS algorithm has significant improvement in the system.
Performance Evaluation Of Adaptive Array Antennas In Cognitive Relay Networkcsijjournal
Adaptive Array Antennas (AAAs) are expected to play a key role in meeting the demands of the wireless communication systems of the future. AAAs in cognitive relay network is proposed to reduce the symbol error rate and improve the system performance. Many algorithms such as wiener solution and least mean square (LMS) will be explained to show how AAAs in cognitive relay network achieves this object. AAAs
at different locations will be investigated under AWGN and Rayleigh fading channel. Moreover, enhancement the system performance by showing the effect of increasing the number of AAAs element at the relay node, increasing the source gain and decreasing the relay gain. In addition, increasing the rate adaptation and number of iterations in LMS algorithm has significant improvement in the system.
Performance Evaluation of Adaptive Array Antennas in Cognitive Relay Networkcsijjournal
Adaptive Array Antennas (AAAs) are expected to play a key role in meeting the demands of the wireless communication systems of the future. AAAs in cognitive relay network is proposed to reduce the symbol error rate and improve the system performance. Many algorithms such as wiener solution and least mean square (LMS) will be explained to show how AAAs in cognitive relay network achieves this object. AAAs at different locations will be investigated under AWGN and Rayleigh fading channel. Moreover, enhancement the system performance by showing the effect of increasing the number of AAAs element at
the relay node, increasing the source gain and decreasing the relay gain. In addition, increasing the rate adaptation and number of iterations in LMS algorithm has significant improvement in the 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
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.
IRJET- Performance Analysis of a Synchronized Receiver over Noiseless and Fad...IRJET Journal
This document summarizes the performance analysis of a synchronized receiver over noiseless and fading channels. It presents a baseband communications system that implements data phase transmission using a single-tone waveform. The behavior of the received signal when transmitted over a noiseless channel and a fading frequency selective channel with additive white Gaussian noise is analyzed. Key plots analyzed include the channel output power spectrum, cross-spectral phase between the equalizer input and output, control signal for the equalizer, and scatter plots of the equalizer input, output, and descrambler output. The analysis shows distortion of the signal due to noise in the fading channel.
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.
Improved Ad-Hoc Networks Using Cooperative DiversityIJCSIT Journal
In this paper an ad-hoc network having source, a
destination and a third station which is a relay is analyzed.
The channels used here are modeled having thermal noise,
Rayleigh fading and path loss. Different methods for
combining and diversity protocols are compared.
Heuristic based adaptive step size clms algorithms for smart antennascsandit
This document summarizes research on heuristic-based adaptive step size complex least mean square (CLMS) algorithms for smart antennas. It presents Benveniste and Mathews algorithms, which use heuristics with CLMS to speed up convergence. Simulations show these algorithms outperform CLMS and augmented CLMS in convergence rate while achieving similar performance in terms of half power beamwidth and side lobe level of the array factor. The key advantage of these algorithms is faster convergence for the output signal of smart antenna systems compared to baseline algorithms like CLMS.
This document proposes and evaluates a new chaotic communication system called Correlation Delay Shift Keying (CDSK). It summarizes the characteristics and advantages of using chaotic signals for communication. It then describes the CDSK system and compares its bit error rate performance using two different chaos maps (Tent map and a newly proposed Boss map) in additive white Gaussian noise and Rayleigh fading channels. The results show that the Boss map provides better bit error rate performance than the Tent map.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
PERFORMANCE EVALUATION OF BER FOR AWGN, AWGN MULTIPATH AND RAYLEIGH FADING CH...IJEEE
This document evaluates the performance of bit error rate (BER) for different digital modulation techniques over additive white Gaussian noise (AWGN), AWGN multipath, and Rayleigh fading channels. It presents simulation results comparing the BER of binary phase-shift keying (BPSK) and quadrature phase-shift keying (QPSK) modulation under varying signal-to-noise ratio (SNR) levels for AWGN and AWGN multipath channels, and under varying Doppler shift levels for Rayleigh fading channels. The results show that BPSK has better BER performance than QPSK, and that BER is lowest for AWGN channels and highest for Rayleigh fading channels.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
Telecommunication System Engineering NotesHaris Hassan
Telecommunications engineering, or telecoms engineering, is an engineering discipline centered on electrical and computer engineering which seeks to support and enhance telecommunication systems.
Physical security with power beacon assisted in half-duplex relaying networks...TELKOMNIKA JOURNAL
In this research, we proposed and investigated physical security with power beacon assisted in half-duplex relaying networks over a Rayleigh fading channel. In this model, the source (S) node communicates with the destination (D) node via the helping of the intermediate relay (R) node. The D and R nodes harvest energy from the power beacon (PB) node in the presence of a passive eavesdropper (E) node. Then we derived the integral form of the system outage probability (OP) and closed form of the intercept probability (IP). The correctness of the analytical of the OP and IP is verified by the Monte Carlo simulation. The influence of the main system parameters on the OP and IP also is investigated. The research results indicated that the analytical results are the same as the simulation ones.
Mitigating Interference to GPS Operation Using Variable Forgetting Factor Bas...IJCNCJournal
In this paper, an interference method based on signal processing is proposed. The approach is based on
utilizing the maximum likelihood properties of the received signal. The approach is built on maximizing the
probability of the desired data. The GPS data, which is constructed using Binary Phase Shift Keying
(BPSK) modulation, is transmitted as “1’s” and as “0’s.” carried on 1575.42MHz carrier called the L1
frequency. The statistics of the GPS data and interference are utilized in terms of their distribution and
variance. The statistics are used to update (adaptively) the forgetting factor (Lambda) of the Recursive
Least Squares (RLS) filter. The proposed method is called Maximum Likelihood Variable Forgetting Factor
(ML VFF). The adaptive update takes on assigning lambda to the maximum of the probabilities of the
symbols based on the statistics mentioned.
This document analyzes and compares the performance of different adaptive beamforming techniques for smart antennas. It describes switched beamforming, which uses fixed beams, and adaptive beamforming techniques that use algorithms like LMS, SMI, RLS, CGA, CMA, and LSCMA to form an adaptive beam. It simulates these algorithms using MATLAB for a uniform linear array and compares their ability to direct the main beam towards the desired user while nulling interference. The LMS, SMI, RLS, CMA and LSCMA algorithms are found to perform well at directing the beam to the desired user, with LMS having good interference rejection and RLS providing the fastest convergence but highest computational cost.
Discrete wavelet transform-based RI adaptive algorithm for system identificationIJECEIAES
In this paper, we propose a new adaptive filtering algorithm for system identifica- tion. The algorithm is based on the recursive inverse (RI) adaptive algorithm which suffers from low convergence rates in some applications; i.e., the eigenvalue spread of the autocorrelation matrix is relatively high. The proposed algorithm applies discrete-wavelet transform (DWT) to the input signal which, in turn, helps to overcome the low convergence rate of the RI algorithm with relatively small step-size(s). Different scenarios has been investigated in different noise environments in system identification setting. Experiments demonstrate the advantages of the proposed DWT recursive inverse (DWT-RI) filter in terms of convergence rate and mean-square-error (MSE) compared to the RI, discrete cosine transform LMS (DCT-LMS), discretewavelet transform LMS (DWT-LMS) and recursive-least-squares (RLS) algorithms under same conditions.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Application of smart antenna interference suppression techniques in tdscdmamarwaeng
This document discusses the application of smart antenna interference suppression techniques in TD-SCDMA systems. It first provides background on TD-SCDMA and smart antenna technology. It then describes two adaptive beamforming algorithms - LMS and RLS - and simulates their performance at interference suppression in MATLAB. The simulation results show that both algorithms can effectively form a main beam towards the desired user and nulls towards interferers. RLS converges faster than LMS, though it has higher computational complexity. The study demonstrates that smart antenna techniques can improve signal quality in TD-SCDMA systems by suppressing interference.
DIGITAL WAVE FORMULATION OF THE PEEC METHODPiero Belforte
This document presents a digital wave formulation (DWF) method for solving the quasi-static partial element equivalent circuit (PEEC) method in the time domain. The standard PEEC model is transformed into a wave digital network by using wave variables and defining wave digital circuit elements corresponding to inductors, capacitors, resistors, sources, and connections. This allows the PEEC model to be solved as a wave digital network using a digital wave simulator (DWS). A numerical example compares the proposed DWF-PEEC solver to a standard SPICE solver, showing the DWF-PEEC method provides accurate results with significant speed-up in computation time.
PERFORMANCE EVALUATION OF ADAPTIVE ARRAY ANTENNAS IN COGNITIVE RELAY NETWORK csijjournal
Adaptive Array Antennas (AAAs) are expected to play a key role in meeting the demands of the wireless communication systems of the future. AAAs in cognitive relay network is proposed to reduce the symbol error rate and improve the system performance. Many algorithms such as wiener solution and least mean square (LMS) will be explained to show how AAAs in cognitive relay network achieves this object. AAAs at different locations will be investigated under AWGN and Rayleigh fading channel. Moreover, enhancement the system performance by showing the effect of increasing the number of AAAs element at the relay node, increasing the source gain and decreasing the relay gain. In addition, increasing the rate adaptation and number of iterations in LMS algorithm has significant improvement in the system.
Performance Evaluation Of Adaptive Array Antennas In Cognitive Relay Networkcsijjournal
Adaptive Array Antennas (AAAs) are expected to play a key role in meeting the demands of the wireless communication systems of the future. AAAs in cognitive relay network is proposed to reduce the symbol error rate and improve the system performance. Many algorithms such as wiener solution and least mean square (LMS) will be explained to show how AAAs in cognitive relay network achieves this object. AAAs
at different locations will be investigated under AWGN and Rayleigh fading channel. Moreover, enhancement the system performance by showing the effect of increasing the number of AAAs element at the relay node, increasing the source gain and decreasing the relay gain. In addition, increasing the rate adaptation and number of iterations in LMS algorithm has significant improvement in the system.
Performance Evaluation of Adaptive Array Antennas in Cognitive Relay Networkcsijjournal
Adaptive Array Antennas (AAAs) are expected to play a key role in meeting the demands of the wireless communication systems of the future. AAAs in cognitive relay network is proposed to reduce the symbol error rate and improve the system performance. Many algorithms such as wiener solution and least mean square (LMS) will be explained to show how AAAs in cognitive relay network achieves this object. AAAs at different locations will be investigated under AWGN and Rayleigh fading channel. Moreover, enhancement the system performance by showing the effect of increasing the number of AAAs element at
the relay node, increasing the source gain and decreasing the relay gain. In addition, increasing the rate adaptation and number of iterations in LMS algorithm has significant improvement in the 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
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.
IRJET- Performance Analysis of a Synchronized Receiver over Noiseless and Fad...IRJET Journal
This document summarizes the performance analysis of a synchronized receiver over noiseless and fading channels. It presents a baseband communications system that implements data phase transmission using a single-tone waveform. The behavior of the received signal when transmitted over a noiseless channel and a fading frequency selective channel with additive white Gaussian noise is analyzed. Key plots analyzed include the channel output power spectrum, cross-spectral phase between the equalizer input and output, control signal for the equalizer, and scatter plots of the equalizer input, output, and descrambler output. The analysis shows distortion of the signal due to noise in the fading channel.
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PERFORMANCE EVALUATION OF ADAPTIVE ARRAY ANTENNAS IN COGNITIVE RELAY NETWORK
1. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
15
PERFORMANCE EVALUATION OF ADAPTIVE ARRAY
ANTENNAS IN COGNITIVE RELAY NETWORK
Eman Sadik1
, Mona Shokair2
, Abd Elmaged Sharshar3
and Said Elhalafawy4
1,2,3,4
Department of Electronics and Electrical Communication, Faculty of Electronic
Engineering, El- Menoufia University, Menouf, Egypt.
ABSTRACT
Adaptive Array Antennas (AAAs) are expected to play a key role in meeting the demands of the wireless
communication systems of the future. AAAs in cognitive relay network is proposed to reduce the symbol
error rate and improve the system performance. Many algorithms such as wiener solution and least mean
square (LMS) will be explained to show how AAAs in cognitive relay network achieves this object. AAAs
at different locations will be investigated under AWGN and Rayleigh fading channel. Moreover,
enhancement the system performance by showing the effect of increasing the number of AAAs element at
the relay node, increasing the source gain and decreasing the relay gain. In addition, increasing the rate
adaptation and number of iterations in LMS algorithm has significant improvement in the system.
KEYWORDS
Adaptive Array Antennas, cognitive relay network and least mean square algorithm
1. INTRODUCTION
Cognitive radio is used to designate intelligent wireless communication system that is able to
adapt changes occurring in the surrounding environment [1]. It allows Secondary User (SU)
network to coexist with Primary User (PU) network through spectrum sharing, provided that the
secondary spectrum access will not affect the PUs performance [2], [3].
To enhance cognitive radio performance, the cooperative communications that it’s used in [4],
where one or more nodes help the communication between source and destination by acting as
relays, achieve spatial diversity even in a network composed of a single antenna device. In [5],
three protocols of cooperative communications are presented; Amplify and Forward (AF),
Decode and Forward (DF) and Adaptive Relay Protocol (ARP). In the AF protocol, the relay
amplifies the received signal and forwards it to the destination. In the DF protocol, the relay tries
to decode the source message and then re-encodes and forwards it to the destination. ARP is
used to overcome the disadvantage of these two protocols. In our system, AF protocol is used as
its low complexity than the other mentioned.
Another critical issue in cognitive radio is to improve the performance of the system by using
AAAs [6-8]. AAAs is one of the key technologies that are expected to dramatically improve
future wireless communication systems because it has the potential to expand coverage, increase
capacity and improve signal quality. AAAs algorithms, which use reference signal (desired
signal) will be explained in this paper. Other AAAs algorithms, which doesn’t use reference
signal are not considered here. Types of AAAs algorithms used with desired signal are wiener
solution, method of steepest descent, Least Mean Squares (LMS), Normalized Least Mean
2. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
16
Squares (NLMS) and Recursive Least Square (RLS). Wiener solution and LMS algorithms will
be used in this paper. In these algorithms, desired signal is sent during training period. By using
the received desired signal at AAAs, optimum weights can be computed. After the training
period, data is sent and AAAs use the weights computed previously to process the received
signal. AAAs in cognitive relay network will be analysis in this paper to give more improvement
in the system performance.
The reminder of this paper is organized as follows: Section II describes the system model for
the analysis of AAAs in cognitive relay network including wiener solution and LMS algorithms.
Simulation results are illustrated in Section III. Finally, conclusions are made in Section V.
2. SYSTEM MODEL
Figure 1. Adaptive array antenna in cognitive relay network.
AAAs in cognitive relay network at the source, relay and destination is illustrated in Figure 1,
where S, R and D denotes the source, relay and destination respectively. The relay node is
randomly located between the source and the destination to provide most enhancements for the
link. The common channels of S and D will be reserved for the usage of direct link. The
channels used by R for receiving and transmitting are called indirect channels. They are used for
amplifying the received data, and then retransmit it to the destination node.
An antenna array consists of N identical antenna elements arranged in a particular geometry,
where the geometry of the array determines the amount of coverage in a spatial region. AAAs
algorithms, which use the desired signal, will be used in this paper. In these algorithms, desired
signal is sent and by using the received desired signal at AAAs, optimum weights can be
computed. Then, data is sent and AAAs uses the previously computed weights to process the
received signal.
3. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
17
In the following AAAs algorithms are described which try to minimize the mean square error
between the desired signal d (k) and the array output signal y (k).
2.1. Wiener Solution
The error signal e (k) can be expressed as the difference between y (k) and d (k) at sampling
instant k as follows [8],
e ( k) = d(k) –y(k) (1)
Where d(k) is the desired signal and the mean squared error is defined by,
J(k) = E[|e(k)|ଶ
] = E[หd(k) – y(k)ห
ଶ
] (2)
The optimum weights control can be given as
)݇(ݓ௧. = ܴ௫௫(k)ିଵ
ݎ௫ௗ(݇) (3)
Where ܴ௫௫ = )݇(ݔ[ܧ்
()݇(ݔ∗
)்
] is the autocorrelation matrix of the input signal )݇(ݔ, ݎ௫ௗ =
)݇(ݔ()݇(݀[ܧ்
)∗
] is the cross correlation matrix between the complex conjugate of the input
signal and the desired signal.
The output y(k) of linear combination of data for M elements at time k is denoted as,
y(k) = ∑ ݓ
ெ
ୀଵ (݇)ݔ(݇) (4)
In vector form the last equation can be written as,
Y(k) = X(k)்
ܹ(݇) (5)
Where (. )்
is the transpose operator.
2.2. LMS Algorithm
The block diagram of Least Mean Square algorithm is represented in Figure 2. The LMS is an
iterative beamforming algorithm that uses the estimate of the gradient vector from the available
data. The weight vector is updated in accordance with an algorithm that adapts to the incoming
data. The simplicity of LMS algorithm comes from the fact that it doesn’t require measurements
of the correlation functions nor matrix inversion. The updated weight is denoted by [9],
w(k+1) = w(k) + 2ߤ ݁ )݇(ݔ∗
(݇) (6)
where μ is defined as the rate of adaptation, controlled by the processing gain of the antenna
array (step size parameter) and e∗
(k) is the complex conjugate of error signal.
4. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
18
Figure 2. Block diagram representation of LMS algorithm.
3. SIMULATION RESULTS
In this section, the numerical results supporting the analysis of adaptive array antenna in
cognitive relay network are presented. Here, the cognitive relay network is demonstrated
consisting of a source, a destination and a cognitive relay node between them. The performance
of AAAs in cognitive relay network is illustrated using wiener solution and LMS algorithms
under AWGN and Rayleigh fading channel. Assume that, the number of transmitted symbols N
is equal to10ସ
. For simplicity, it is assumed that, the same transmitted power of source and
relay will be applied.
In the following the effect of many parameters will be studied as follows:
3.1. Effect of AAAs at different locations in cognitive relay network
Figure 3 compares Symbol Error Rate (SER) of AAAs at source, relay and destination node
using wiener solution algorithm. Numerical results are obtained by transmitted power of source
௦ =
ଶ
, transmitted power of relay =
ଶ
. As shown in this figure, locating AAAs at the
source has better performance than locating AAAs at the relay and destination.
5. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
19
Figure 3. SER of AAAs at different locations in cognitive relay network.
As the AAAs at the relay node using wiener solution algorithm has the worst performance as
shown in Figure 3, some parameters are studied to enhance the performance of the system.
3.1.1. Increasing the source node gain
Figure 4 shows the numerical results of increasing the antenna gain at the source (ܩ௦) node
when AAAs at the relay node under using wiener solution algorithm. From this figure, it can be
concluded that significant improvement in performance is observed by increasing (ܩ௦) .
Figure 4. Impact of increasing the source gain when AAAs at the relay node.
3.1.2. Decreasing the relay node gain
The effect of decreasing the antenna gain at the relay (ܩ) is illustrated in Figure 5 when AAAs
at the relay node using wiener solution algorithm. It is shown in this figure that improving the
system performance is obtained by decreasing ܩ which explained by occurring interference on
the signal.
0 2 4 6 8 10 12 14 16 18 20
10
-5
10
-4
10
-3
10
-2
10
-1
10
0
SNR(dB)
SER
Wiener Solution Algorithm
AAAs at the Source
AAAs at the Relay
AAAs at the Destination
-10 -8 -6 -4 -2 0 2 4 6 8 10
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
SNR(dB)
SER
AAAs at the Relay Node using Winner Solution Algorithm
Gs=Gt/2
Gs=2Gt/3
Gs=3Gt/4
6. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
20
Figure 5. Effect of decreasing the relay gain when AAAs at the relay node.
3.1.3. Increasing AAAs elements
Figure 6 depicts the impact of increasing the number of antennas element of AAAs at the relay
node. We can conclude from this figure that, the performance of the system using AAAs with
three antennas element outperforms using AAAs with two antennas element.
Figure 6. SER at different AAAs elements.
3.1.3.1. Effect of different types of fading channels and noise
The simulative results of AAAs at the source node using wiener solution algorithm under
different fading channels are illustrated in Figure 7. For instance, at SNR =8dB, the SER is
approximately about 10ିଷ
under AWGN, 10ିଶ
under Rayleigh fading channel and 10ିଵ
under
-10 -8 -6 -4 -2 0 2 4 6 8 10
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
0.65
0.7
0.75
SNR(dB)
SER
AAAs at the Relay Node using Winner Solution Algorithm
Gr=Gt/4
Gr=Gt/3
Gr=Gt/2
-10 -8 -6 -4 -2 0 2 4 6 8 10
0.35
0.4
0.45
0.5
0.55
0.6
0.65
0.7
0.75
SNR(dB)
SER
AAAs at the Relay Node using Wiener Solution Algorithm
AAAs with 2 antennas element
AAAs with 3 antennas element
7. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
21
AWGN plus Rayleigh fading channel. The numerical results indicate that AAAs at the source
under AWGN outperforms the other types.
Figure 7. AAAs at the source node under different types of fading channel using wiener
solution.
The effect of different fading channels of AAAs at the source using LMS algorithm is depicted
in figure 8. For instance, at SNR = 15dB, the SER is approximately 10ିଶ
under AWGN and
10ି.ହ
under Rayleigh fading channel. The results show that AAAs at the source under AWGN
has better performance than under Rayleigh fading channel.
Figure 8. AAAs at the source node under different types of fading channel using LMS algorithm.
3.1.3.2. Effect of different step size parameter in LMS algorithm.
Figure 9 provides AAAs at the source using LMS algorithm with AWGN under different step
size parameters. As shown in this figure, by increasing the step size parameter, enhancing the
performance of the system.
0 2 4 6 8 10 12 14 16 18 20
10
-5
10
-4
10
-3
10
-2
10
-1
10
0
SNR(dB)
SER
AAAs at the Source using Wiener Solution Algorithm
Rayleigh Fading Channel
AWGN
Rayleigh Fading Channel+AWGN
10 15 20 25 30 35
10
-4
10
-3
10
-2
10
-1
10
0
SNR(dB)
SER
AAAs at the Source using LMS Algorithm
AWGN
Rayleigh Fading Channel
8. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
22
Figure 9. Compares different step size parameter in LMS algorithm.
3.1.3.3. Effect of different number of iterations in LMS algorithm.
AAAs at the source using LMS algorithm with AWGN under various number of iteration is
shown in Figure 10. From this figure, it’s found that; the performance of the system is improved
by increasing the number of iterations.
Figure 10. Shows different number of iteration in LMS algorithm.
3. CONCLUSIONS
In this paper, Adaptive array antennas in cognitive relay network are presented to enhance the
performance of the network. Wiener solution and least mean square algorithms are analyzed to
calculate the optimum weights. Putting AAAs at different locations such as at the source, relay
and destination are analytically derived. In addition, the system enhancement is investigated
under AWGN and Rayleigh fading channel is proposed. Moreover, increasing the step size
parameter and the number of iteration in LMS algorithm, improve the system performance. The
10 15 20 25 30 35 40
10
-4
10
-3
10
-2
10
-1
10
0
SNR(dB)
SER
AAAs at the Source using LMS with AWGN
mu=0.01
mu=0.02
mu=0.03
mu=0.04
0 2 4 6 8 10 12 14
10
-5
10
-4
10
-3
10
-2
10
-1
10
0
SNR(dB)
SER
AAAs at the Source using LMS with AWGN
No of Iteration=100
No of Iteration=1000
9. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
23
simulation results show that combining adaptive array antennas and cognitive relay network
present significant improvement in the performance of the system.
REFERENCES
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Authors
Eman Sadik was born in Menoufia, Egypt, in 1990. she received her B.Sc. degree in
electronics and electrical Communications engineering from the Faculty of Electronic
Engineering, Menoufia University, Egypt, in 2009.she is an Electrical Engineer at
Faculty of electronic engineer, Menoufia University. Her graduation project was about
open eNB with excellent degree. Her research interests include wireless mobile
communications and next generation networks.
Mona Shokair received the B.Sc., and M.Sc. degrees in electronics engineering from
Menoufia University, Menoufia,Egypt, in 1993, and 1997, respectively. She received the
Ph.D. degree from Kyushu University, Japan, in 2005. She received VTS chapter IEEE
award from Japan, in 2003. She published about 40 papers until 2011. She received the
Associated Professor degree in 2011. Presently, she is an Associated Professor at
Menoufia University. Her research interests include adaptive array antennas, CDMA
system, WIMAX system, OFDM system, and next generation networks.
Abdul-Mageed Sharshar received the B.Sc., and M.Sc. degrees in electronics
engineering from Menoufia University, Menoufia, Egypt, in 1978, and 1982,
respectively. He received the Ph.D. degree from England, London University, in 1991.
Presently, he is Lecturer at faculty of electronic engineering, Menoufia University. He
has published several scientific papers in national and international conferences and
journals. His current research areas of interest include Antennas and Microwaves.
10. Circuits and Systems: An International Journal (CSIJ), Vol.1, No.4, October 2014.
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Said Elhalafawy received the B.Sc., and M.Sc. degrees in electronics engineering from Menoufia
University,Menoufia, Egypt, in 1978, and 1984, respectively. He received the Ph.D.
degree from Plzen, Czech Republic, in 1990. Presently, he is the dean and Professor at
faculty of electronic engineering, Menoufia University. He has published several
scientific papers in national and international conferences and journals. His current
research areas of interest include image processing, speech processing, digital
communications and electromagnetic applications.