针对STBC-OFDM信号盲识别中存在着识别所需样本数多、对频偏敏感和不适用于单接收天线等问题,提出一种基于FOLP(Fourth Order Lag Product)的识别方法.根据不同空时分组码元素的相关性,推导了接收信号的FOLP,构造了基于FOLP的峰值检测算...针对STBC-OFDM信号盲识别中存在着识别所需样本数多、对频偏敏感和不适用于单接收天线等问题,提出一种基于FOLP(Fourth Order Lag Product)的识别方法.根据不同空时分组码元素的相关性,推导了接收信号的FOLP,构造了基于FOLP的峰值检测算法.推导和仿真结果表明,该算法能够在单接收天线下运行,且不需要知道信道信息、噪声信息、调制信息以及OFDM块的起始位置;且该算法不受调制方式的影响,对时延、相位噪声和频率偏移鲁棒性能好,能够应用于认知无线电、频谱监控等工程领域中.展开更多
Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code (STBC) systems is proposed by us...Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code (STBC) systems is proposed by using the ordinary independent component analysis (ICA). This method cannot work when specific complex modulations are employed since the assumption of mutual independence cannot be satisfied. The analysis shows that source signals, which are group-wise independent and use multi-dimensional ICA (MICA) instead of ordinary ICA, can be applied in this case. Utilizing the block-diagonal structure of the cumulant matrices, the JADE algorithm is generalized to the multidimensional case to separate the received data into mutually independent groups. Compared with ordinary ICA algorithms, the proposed method does not introduce additional ambiguities. Simulations show that the proposed method overcomes the drawback and achieves a better performance without utilizing coding information than channel estimation based algorithms.展开更多
在单接收天线下,针对频率选择性衰落信道下空时分组码(STBC)的盲识别问题,提出了一种基于Kolmogorov-Smirnov(K-S)检测的有效算法。该算法以经验累积分布函数作为特征函数,通过K-S检测经验累积分布函数之间的距离,达到识别空时分组码的...在单接收天线下,针对频率选择性衰落信道下空时分组码(STBC)的盲识别问题,提出了一种基于Kolmogorov-Smirnov(K-S)检测的有效算法。该算法以经验累积分布函数作为特征函数,通过K-S检测经验累积分布函数之间的距离,达到识别空时分组码的目的。在不同调制方式、采样因子和置信区间的条件下分别对算法进行仿真并讨论其性能,结果表明,该算法性能较好,在信噪比大于6 d B时可达到90%以上的正确识别概率,在非合作通信方面具有一定的实用价值。展开更多
针对多输入单输出(multiple input single output,MISO)系统中的空时分组码(space-time block code,STBC)盲识别问题,提出了一种基于卷积神经网络(convolutional neural network,CNN)的串行STBC识别方法。首先,结合STBC识别问题提出了基...针对多输入单输出(multiple input single output,MISO)系统中的空时分组码(space-time block code,STBC)盲识别问题,提出了一种基于卷积神经网络(convolutional neural network,CNN)的串行STBC识别方法。首先,结合STBC识别问题提出了基本CNN(CNN basic,CNN-B)框架;然后在分析STBC相关性的基础上,针对空间复用和Alamouti信号混叠问题,设计了基于相关性的CNN(CNN based on correlation,CNN-BC)模型;最后将STBC数据集输入到网络模型中,完成网络的训练和识别测试。仿真结果表明,相比于基于特征提取的传统算法,该方法将可识别的STBC扩展到了6种,并且在低信噪比下的识别准确率更高,识别过程可控制在微秒级别,具有较高的工程应用价值。展开更多
文摘针对STBC-OFDM信号盲识别中存在着识别所需样本数多、对频偏敏感和不适用于单接收天线等问题,提出一种基于FOLP(Fourth Order Lag Product)的识别方法.根据不同空时分组码元素的相关性,推导了接收信号的FOLP,构造了基于FOLP的峰值检测算法.推导和仿真结果表明,该算法能够在单接收天线下运行,且不需要知道信道信息、噪声信息、调制信息以及OFDM块的起始位置;且该算法不受调制方式的影响,对时延、相位噪声和频率偏移鲁棒性能好,能够应用于认知无线电、频谱监控等工程领域中.
基金supported by the National Natural Science Foundation of China (61201282)
文摘Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code (STBC) systems is proposed by using the ordinary independent component analysis (ICA). This method cannot work when specific complex modulations are employed since the assumption of mutual independence cannot be satisfied. The analysis shows that source signals, which are group-wise independent and use multi-dimensional ICA (MICA) instead of ordinary ICA, can be applied in this case. Utilizing the block-diagonal structure of the cumulant matrices, the JADE algorithm is generalized to the multidimensional case to separate the received data into mutually independent groups. Compared with ordinary ICA algorithms, the proposed method does not introduce additional ambiguities. Simulations show that the proposed method overcomes the drawback and achieves a better performance without utilizing coding information than channel estimation based algorithms.
文摘在单接收天线下,针对频率选择性衰落信道下空时分组码(STBC)的盲识别问题,提出了一种基于Kolmogorov-Smirnov(K-S)检测的有效算法。该算法以经验累积分布函数作为特征函数,通过K-S检测经验累积分布函数之间的距离,达到识别空时分组码的目的。在不同调制方式、采样因子和置信区间的条件下分别对算法进行仿真并讨论其性能,结果表明,该算法性能较好,在信噪比大于6 d B时可达到90%以上的正确识别概率,在非合作通信方面具有一定的实用价值。
文摘针对多输入单输出(multiple input single output,MISO)系统中的空时分组码(space-time block code,STBC)盲识别问题,提出了一种基于卷积神经网络(convolutional neural network,CNN)的串行STBC识别方法。首先,结合STBC识别问题提出了基本CNN(CNN basic,CNN-B)框架;然后在分析STBC相关性的基础上,针对空间复用和Alamouti信号混叠问题,设计了基于相关性的CNN(CNN based on correlation,CNN-BC)模型;最后将STBC数据集输入到网络模型中,完成网络的训练和识别测试。仿真结果表明,相比于基于特征提取的传统算法,该方法将可识别的STBC扩展到了6种,并且在低信噪比下的识别准确率更高,识别过程可控制在微秒级别,具有较高的工程应用价值。