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Blind Adaptive Multiuser Detection Based on FIAPI Algorithm

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Wuhan University Journal of Natural Sciences 2020年第1期25卷 59-64页

作者： XIAO Wenshuai RU Guobao gan liangcai School of Electronic Information Wuhan UniversityWuhan 430072HubeiChina

Multiuser detection technology is currently one of the effective ways to suppress multiple access interference and near-far effects. Firstly, through selecting a simple compensation matrix, fast improved approximation power iteration(FIAPI) subspace tracking optimization algorithm is proposed. Secondly, for the disadvantage of high computational complexity of Kalman filtering algorithm, Kalman for blind adaptive multiuser detector based on FIAPI subspace tracking algorithm is designed. The simulation experiments show that the convergence and anti-interference ability of the blind adaptive multiuser detector based on FIAPI algorithm is greatly improved, and the average signal-to-interference ratio of the FAPI algorithm is improved by about 0.7 dB, which is higher than the average signal-to-interference ratio of the orthogonal projection approximation subspace tracking(OPAST) algorithm 2 dB or so.

关键词： fast improved approximate power iteration(FIAPI) Kalman filtering multiuser detection subspace tracking

Influence of CNN Structure Parameters on Blind Equalization of Shortwave Channels

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Wuhan University Journal of Natural Sciences 2021年第1期26卷 102-106页

作者： LIU Qi SUN Wenqiang RU Guobao gan liangcai School of Electronic and Information Wuhan UniversityWuhan 430072HubeiChina

Aiming at the severe inter-symbol interference and high bit error rate in short-wave fast time-varying channels,this paper designs a short-wave channel blind equalizer based on Convolution Neural Network(CNN),and analyzes the influence of parameters in CNN structure on channel equalization,such as the number of convolution layers,the depth of convolution layer and the size of the convolution kernel *** simulating two typical short-wave time-varying channel,Rayleigh flat fading and frequency selective fading channels,we have the following results:1)Compared with the Recurrent Neural Network(RNN)structure equalizer,the CNN has higher accuracy during the training process,the convergence speed is faster,and the stability after convergence is higher.2)Under the condition of simulation,the CNN-based short-wave channel blind equalizer designed in this paper can effectively extract input signal when using 2×3×3 convolution kernel size and 2-layer convolutional *** characteristics of the classification layer improve the equalization performance while reducing the complexity of CNN structure.3)For the short-wave channel,the error rate of Convolution Neural Network Equalizer(CNNE)is lower than that of Recurrent Neural Network Equalizer(RNNE)under the same SNR.

关键词： channel equalization short-wave fast time-varying channel Convolution Neural Network(CNN)

Low Complexity MMSE-SQRD Signal Detection Based on Iteration

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Wuhan University Journal of Natural Sciences 2019年第5期24卷 431-434页

作者： WU Di RU Guobao gan liangcai YU Xuechun LIU Qi School of Electronic Information Wuhan University

Aiming at the problem of high computational complexity of Vertical-BLAST(V-BLAST) algorithm in Multiple-Input Multiple-Output-Orthogonal Frequency Division Multiplexing(MIMO-OFDM) system signal detection, this paper first uses Sorted QR Decomposition(SQRD) iterative operation instead of matrix inversion to reduce the computational complexity of the algorithm, and then considering that the algorithm is greatly affected by noise, Minimum Mean Square Error(MMSE) criterion is used to weaken the noise effect. At the same time, in order to reduce the noise and computational complexity, MMSE and SQRD are combined, which can not only reduce the noise and computational complexity, but also obtain the sub-optimal detection order, thus improving the detection performance of the MIMO-OFDM system. Finally, the numerical simulation of the MMSE-SQRD detection algorithm is carried out. The results show that the Eb/No of MMSE-SQRD algorithm is 2 dB greater than that of the MMSE algorithm and the computational complexity is O(NT3) under the conditions that NT =NR=2 and the BER is 10–2. The detection algorithm satisfies the demand of short wave and wideband wireless communication.

关键词： Multiple-Input Multiple-Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) Minimum Mean Square Error (MMSE) Sorting Orthogonal-Triangular Decoding (SQRD) algorithm the MMSE-SQRD algorithm

Frequency Synthesizer of Short-Wave SFH/MFSK System

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 71-75页

作者： gan liangcai, Bao Yongqiang(College of Electronic Information, Wuha University, Wuhan 430072, China)

The technology of DDS-driven PLL is introduced and a new scheme of frequency synthesizer which is suitable for SW SFH/MFSK System is presented in this paper. Based on the special requirement of SW communication, a model of the scheme is given and the results show that the frequency synthesizer has small frequency insteval (≤0.1 Hz), short switch pierod (<200 ms) and high frequency stability as crystal oseillator.

关键词： Key words frequency synthesizer frequency inteval switch pierod FH communication

Modulation Frequency Optimization in Two-Colar Instruments

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Journal of Systems Engineering and Electronics 2003年第3期14卷 45-48页

作者： Zhao Maotai & gan liangcai School of Electronic Information, Wuhan University, Wuhan 430072, P.R. China School of Electronic Information Wuhan University Wuhan 430072 P.R. China

How to choose modulation frequency in the extra-high frequency geodimeter is directly related to a lot key matters such as distance sensitivity of instruments and degree of technological difficulty of modulation system. This paper analyzes and proves that choice range of modulation frequency can be from 800 MHz up to extra-high frequency with the

关键词： Modulation frequency Two-color instruments Optimization Frequency.

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短波差分跳频通信系统抗多音干扰的性能分析

武汉大学学报（理学版） 2006年第3期52卷 380-384页

作者：项飞甘良才武汉大学电子信息学院湖北武汉430072

针对应用于军事通信的短波差分跳频系统中存在敌意多音干扰的问题,建立了系统的多音干扰模型,采用一种联合-切尔诺夫限的方法,从理论上导出了该系统(无编码)在加性高斯白噪声信道和瑞利衰落信道条件下抗多音干扰的比特误码率性能上界;... 详细信息

针对应用于军事通信的短波差分跳频系统中存在敌意多音干扰的问题,建立了系统的多音干扰模型,采用一种联合-切尔诺夫限的方法,从理论上导出了该系统(无编码)在加性高斯白噪声信道和瑞利衰落信道条件下抗多音干扰的比特误码率性能上界;并采用RS信道编码方法,对无编码系统在瑞利衰落信道下误码率为10-3时出现的差错平板进行了改善.数值结果表明编码后的系统较无编码系统能获得约7 dB的性能增益,有效提高了抗多音干扰的能力.

关键词：短波差分跳频多音干扰联合-切尔诺夫限 RS信道编码

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改进的块复制不等差错保护喷泉码

数据采集与处理 2015年第3期30卷 591-598页

作者：邓在辉同小军甘良才武汉纺织大学数学与计算机学院武汉430200 武汉大学电子信息学院武汉430072

在多媒体传输、深空通信等应用中,由于数据的重要性程度不同,需要喷泉码具有不等差错保护的特性,根据数据重要性给予不同程度的保护。对基于块复制的不等差错保护喷泉码的机制进行了理论分析,提出了改进的信息符号选取策略,让度1编码符... 详细信息

在多媒体传输、深空通信等应用中,由于数据的重要性程度不同,需要喷泉码具有不等差错保护的特性,根据数据重要性给予不同程度的保护。对基于块复制的不等差错保护喷泉码的机制进行了理论分析,提出了改进的信息符号选取策略,让度1编码符号全部在重要信息比特中选取,一定数量的度2编码符号分别在重要信息比特和次要信息比特中选取,从局部上提升对重要信息比特的保护。仿真结果表明,相比于现有的基于块复制的不等差错保护喷泉码,改进方法在进一步提高重要信息比特保护的同时没有降低对次要信息比特的保护,且有更好的不等恢复时间性能。

关键词：喷泉码 LT码不等差错保护块复制

短波跳频FH/QDPSK系统信道自适应监测的研究(Ⅰ)

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系统工程与电子技术 2000年第9期22卷 1-4页

作者：邹学玉甘良才武汉大学电子信息学院 430072

基于短波跳频FH/QDPSK系统的FFT解调 ,利用FFT解调的结果 ,提出了在瑞利衰落信道中对信道的比特误码率BER进行实时自适应监测方法 ,该方法利用伪错外推较好地解决了在较短的监测时间获取较精确的监测结果。模拟结果表明 :采用伪错的线... 详细信息

基于短波跳频FH/QDPSK系统的FFT解调 ,利用FFT解调的结果 ,提出了在瑞利衰落信道中对信道的比特误码率BER进行实时自适应监测方法 ,该方法利用伪错外推较好地解决了在较短的监测时间获取较精确的监测结果。模拟结果表明 :采用伪错的线性外推算法 ,其估值的最大绝对误差不超过 0 89,最大相对误差不超过35 7%。

关键词：信道跳频通信短波通信 FH/QDPSK

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基于混沌的宽间隔跳频序列

通信学报 1999年第4期20卷 72-76页

作者：甘良才吴燕翔武汉大学电子信息学学院武汉430072

提出了一种用混沌映射方法产生党间隔跳频序列的方法，分析了混沌宽间隔跳频序列的平衡特性及汉明相关特性，并讨论了序列的线性复杂度和抗破译能力。实验表明，该跳频序列性能良好，适用于短波跳频系统。

关键词：混沌跳频序列宽间隔保密通信短波跳频系统