摘要
针对跳频频率为2的频率编码与二相编码复合调制信号(2FSK/BPSK)参数难以估计的问题,通过对2FSK/BPSK信号ZAM-GTFR变换的分析,提出了一种参数估计方法。首先对接收信号进行ZAM-GTFR变换,并进行一维搜索获得反映BPSK相位突变的负尖峰,再做快速傅里叶变换,根据基波频率估计相位编码码速率;同时,利用负尖峰出现的频点以及ZAM-GTFR时频图的脊线,对脊线做二值离散以及差分,分别提取2FSK频率及其码速率。仿真分析表明,在讨论的信号模型下,当信号全频段信噪比大于-1dB时,该算法能以正确率优于90%的较高精度估计信号参数。
To solve the problem of estimating the parameters of the hybrid signal combined by binary frequency shift-keying and binary phase shift-keying （2FSK/BPSK）, an approach is presented based on the generalized time-frequency representation of Zhao, Atlas, and Marks （ZAM-GTFR） of 2FSK/ BPSK signal. Firstly, the ZAM-GTFR of the received signal is presented, and the negative peaks re- flecting the phase changes of BPSK are derived, then the code rate of BPSK is estimated by the fast Fourier transform of these peaks. Meanwhile, the frequency locations of the negative peaks and the ridge of ZAM - GTFR after discretization and difference are used to estimate the frequency and code rate of 2FSK. Simulations show that this approach has 90% accuracy when the signal to noise ratio （SNR） is greater than - 1dB under the discussed signal model.
出处
《电子信息对抗技术》
2011年第2期9-14,共6页
Electronic Information Warfare Technology
