一种DCSK通信系统的延迟合并接收方案

提出一种多径衰落信道下DCSK通信系统的延迟合并接收方案. 理论分析和仿真结果证实了该方案的误码性能. 结果表明，和原DCSK通信系统相比，使用了延迟合并接收方案的DCSK通信系统误码性能有所提高；不同接收路径延迟对应的误码性能基本相同；各接收路径采用等增益合并方式时误码性能最好；其理论上限随着接收路径数增加而逐渐降低.     

Blind Extraction of Chaotic Signals by Using the Fast Independent Component Analysis Algorithm

We report the results of using the fast independent component analysis （FastICA） algorithm to realize Mind extraction of chaotic signals. Two cases are taken into consideration： namely, the mixture is noiseless or contaminated by noise. Pre-whitening is employed to reduce the effect of noise before using the FastICA algorithm. The correlation coefficient criterion is adopted to evaluate the performance, and the success rate is defined as a new criterion to indicate the performance with respect to noise or different mixing matrices. Simulation results show that the FastICA algorithm can extract the chaotic signals effectively. The impact of noise, the length of a signal frame, the number of sources and the number of observed mixtures on the performance is investigated in detail It is also shown that regarding a noise as an independent source is not always correct.