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Science China(Information Sciences) 2011年第1期54卷 129-135页

作者： ZHOU ZhiQiang,LI ShaoQian & CHENG YuFan National Key Laboratory of Science and Technology on Communications,University of Electronic Science and Technology of China,Chengdu 610054,China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China Chengdu China

Fast frequency hopping can reduce the degradation caused by *** performance of noise-normalized fast frequency-hopped M-ary orthogonal frequency-shift-keying(FFH/MFSK)receivers over frequency nonselective rayleigh fading channels with partial-band noise jamming is *** of numerical evaluation,a closed-form error probability expression is given based on the theory of complex variables. The simulation results validate the analytical *** is shown that there is an optimum diversity order and the system performance gets better with an increase in the modulation order.

关键词： anti-jamming fast frequency hopping noise normalization combining rayleigh fading

Performance Evaluation of a DS-CDMA System in a rayleigh fading Environment

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World Journal of Engineering and Technology 2016年第1期4卷 1-9页

作者： M. A. Rahman M. M. Alam Md. Khalid Hossain Md. Khairul Islam Khan M. Nasir Uddin Md. Shahinuzzaman Department of Applied Physics Electronics & Communication Engineering Islamic University Kushtia Bangladesh Institute of Electronics Atomic Energy Research Establishment Savar Bangladesh

This work represents the performance evaluation of DS-CDMA in a rayleigh fading environment. Performance analysis was carried out for a DS-CDMA system to evaluate the signal-to-noise ratio (SNR), signal-to-interference ratio (SIR) and bit error rate (BER) for different modulation schemes like ASK, PSK and FSK. Results were evaluated at different data rates and were presented in terms of SNR, SIR and BER. Computer simulation was also carried out by using Matlab to evaluate the signal waveforms with and without addition white Gaussian noise (AWGN). Butterworth filtered waveform was given to get better signal quality. Decoded output waveforms were also evaluated to confirm the simulation.

关键词： DS-CDMA rayleigh fading Performance Analysis SNR BER ASK PSK FSK MATLAB AWGN

Performance Simulation in Time Domain for rayleigh-fading Channels of Mobile Radio systems

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Performance Simulation in Time Domain for Rayleigh-Fading Ch...

CNN demodulation model with cascade parallel crossing for CPM signals

1998 International Conference on Communication Technology

作者： Zhu Hongbo Cao Wei Wan Yan Zhou Wensheng Nanjing University of Posts and Telecommunications

＜正＞Based on researching and describing statistically radio propagation performance in mobile environments with rayleigh distribution,the paper simulated and analyzed the time-domain performance of rayleigh fading m... 详细信息

ISBN: (纸本)7800908275

关键词： Mobile radio channel Time-domain performance Multipath propagation channel rayleigh fading Computer simulation

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The Journal of China Universities of Posts and Telecommunications 2024年第3期31卷 30-42页

作者： Yang Jiachen Duan Ruifeng Li Chengju School of Information Science and Technology Beijing Forestry UniversityBeijing 100083China Engineering Research Center for Forestry-Oriented Intelligent Information Processing of National Forestry and Grassland Administration Beijing 100083China

The continuous phase modulation(CPM)technique is widely used in range telemetry due to its high spectral efficiency and power ***,the demodulation performance of the traditional maximum likelihood sequence detection(MLSD)algorithm significantly deteriorates in non-ideal synchronization or fading *** address this issue,this work proposes a convolutional neural network(CNN)called the cascade parallel crossing network(CPCNet)to enhance the robustness of CPM signals *** CPCNet model employs a multiple parallel structure and feature fusion to extract richer features from CPM *** approach constructs feature maps at different levels,resulting in a more comprehensive training of the model and improved demodulation *** results show that under Gaussian channel,the proposed CPCNet achieves the same bit error rate(BER)performance as MLSD method when there is no timing error,but with 1/4 symbol period timing error,the proposed method has 2 dB demodulation gain compared with CNN and convolutional long short-term memory deep neural network(CLDNN).In addition,under rayleigh channel,the BER of the proposed method is reduced by 5%-87%compared to that of MLSD in the wide signal-to-noise ratio(SNR)region.

关键词： continuous phase modulation(CPM) convolutional neural network(CNN) maximum likelihood sequence detection(MLSD) rayleigh fading timing error

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Lifetime maximization of cooperative networks with mean channel gain information

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 98-103页

作者： YANG Chang-qing,WANG Wen-bo,ZHAO Shuang,PENG Mu-gen School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A simple but effective relay-selection and power-allocation scheme is proposed to maximize the lifetime of decode-and-forward （DF） cooperative networks under the constraint that only the mean channel gain information is available at the transmitters. The new scheme takes both channel state information （CSI） and residual energy information （REI） into consideration. To evaluate the performance of the proposed scheme, three typical relay-selection and power-allocation schemes, i.e., maximum residual energy （MRE）, minimum transmit power （MTP） and equal transmit power （ETP） are considered. Simulation results show that the proposed scheme outperforms the MRE and the MTP in lifetime duration and outage probability, while needing much less signal overhead compared with the ETP.

关键词： cooperative commtmication lifetime relay selection power allocation rayleigh fading

Shortest Link Scheduling in Wireless Networks with Oblivious Power Control

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China Communications 2021年第4期18卷 137-152页

作者： Chunmei Ma Jiguo Yu Baogui Huang Yu Meng School of Computer Science Qufu Normal UniversityRizhao 276826China School of Computer Science and Technology Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Shandong Computer Science Center(National Supercomputer Center in Jinan) Jinan 250014China Shandong Provincial Key Laboratory of Computer Networks Jinan 250014China School of Computer Science&Technology Georgia State UniversityGA 30303USA

Link scheduling has always been a fundamental problem in wireless networks for its direct impacts on the performance of wireless networks such as throughput capacity,transmission delay,lifetime,*** work is mainly established under graphbased models,which are not only impractical but also incorrect due to the essentially fading characteristics of *** this paper,we study the shortest link scheduling problem under two more realistic models,namely the signal to interference plus noise ratio(SINR)model and the rayleigh fading *** propose a centralized square-based scheduling algorithm(CSSA)with oblivious power control under the SINR model and prove its correctness under both the SINR model and the rayleigh fading ***,we extend CSSA and propose a distributed square-based scheduling algorithm(DSSA).Note that DSSA adopts CSMA/CA so that a wireless node can compete for the wireless channel before starting its *** also show theoretical analysis and conduct extensive simulations to exhibit the correctness and efficiency of our algorithms.

关键词： link scheduling SINR rayleigh fading wireless networks wireless communications

Adaptive Power and Bit Allocation in Multicarrier Systems

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Journal of Electronic Science and Technology of China 2007年第1期5卷 13-17页

作者：霍永青彭启琮邵怀宗 School of Communication and Information Engineering University of Electronic Science and Technology of China

We present two adaptive power and bit allocation algorithms for multicarrier systems in a frequency selective fading environment. One algorithm allocstes bit based on maximizing the channel capacity, another allocates bit based on minimizing the bit-error-rate （BER）. Two algorithms allocate power based on minimizing the BER. Results show that the proposed algorithms are more effective than Fischer＇s algorithm at low average signal-to-noise ration （SNR）. This indicates that our algorithms can achieve high spectral efficiency and high communication reliability during bad channel state. Results also denote the bit and power allocation of each algorithm and effects of the number of subcarriers on the BER performance.

关键词： adaptive loading multicarrier modulation rayleigh fading frequency selective

A New Macroscopic Multiple Input Multiple Output （MIMO） System

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A New Macroscopic Multiple Input Multiple Output （MIMO） Sy...