论文部分内容阅读
针对非合作通信系统中,多径信道下含有导频的正交频分复用(OFDM)信号子载波调制方式难识别的问题,提出了一种OFDM信号子载波调制方式识别的新方法.该方法首先运用4阶与2阶累积量的组合特征,去除OFDM子载波信号中的空载波信号,然后利用4阶累积量和6阶累积量的组合特征,滤除纯导频子载波信号和部分混有导频的调制子载波信号,最后基于改进的减法聚类方法,对提取出来的受导频影响较小的调制子载波信号进行调制方式识别.实验仿真结果表明,该方法在多径信道条件下具有稳健的识别性能.
Aiming at the problem that OFDM subcarrier modulation scheme with pilots in multipath channel is difficult to identify in noncooperative communication systems, a new method of OFDM subcarrier modulation scheme identification is proposed. In this method, the combination of the fourth order and the second order cumulants is used to remove the null carrier signal from the OFDM subcarrier signal. Then, the combination of the fourth order cumulant and the sixth order cumulant is used to filter out the pure pilot subcarrier signal and part Finally, based on the improved subtractive clustering method, the modulated subcarrier signals that are less affected by the pilot signal are identified by the modulation scheme recognition.Experimental results show that this method is effective in multipath channel Under the conditions of a robust recognition performance.