单通道混合信号的幅度估计算法

摘要

针对非协作通信场合中同调制参数的MSK单通道混合信号的幅度估计问题进行研究.在MSK混合信号的循环谱推导的基础上,通过搜索零频率处循环频率轴上的大强度谱线进行混合信号的幅度估计,利用循环谱算法中的泄漏谱包络辅助来消除谱线选择时存在的模糊问题,并通过大强度谱线位置的泄漏谱包络值来修正相应位置的循环谱幅度,以提高估计精度.仿真结果表明在信噪比大于-15dB时,该方法对功率差异不大的混合信号幅度具有较高的估计精度.该算法无需任何先验信息,适用于低信噪比环境,具有实用价值.%Aimed at non-cooperative communication situations an amplitude estimating question for single channel MSK mixing signals with the same modulating parameters was studied. Based on the derivation of cyclic spectrum for MSK mixture, amplitudes of mixing signals were estimated by searching high-intensity spectral lines along cyclic frequency axis at zero frequency. The envelop of leakage spectrum introduced by fast cyclic spectrum calculation was applied to eliminate the illegibility of spectral line selection. The envelop values of leakage spectrum located at high-intensity spectral lines were used to correct the corresponding amplitudes of cyclic spectrum in order to improve estimating accuracy. Simulation results show its good performance for mixing signals without large power difference when the SNR is greater than -15dB. It is worthy for lower SNR applications without any prior information.