时相调制的陷波滤波技术研究

摘要

Considering the power spectrum of time-phase modulation (TPM), this paper presents a notch filter design technique which can extract the phase change characteristics of TPM. The notch filter is designed according to the parameters of TPM signals. The received TPM signals are filtered by the notch filter, which can weaken the amplitude of time-phase modulation signals at the carrier frequency point and highlight the amplitude at phase change period at the same time. So the phase change information is converted into the amplitude information that can be detected through some amplitude threshold. Finally, the detailed simulation and analysis on notch filter effect, BER performance and bandwidth efficiency are presented. The simulation results show that the TPM system adopting notch filter technology can effectively recover the input digital information and improve the bandwidth efficiency, while maintaining the system transmission performance.%针对时相调制功率谱的特殊性，设计了一种能够提取时相调制相位突变特征的陷波滤波技术。根据输入的时相调制信号参数，设计对应的陷波滤波器；然后对接收信号进行滤波，利用陷波特性将相位突变时间段内的信号幅度突显出来，从而将时相调制信号的相位信息转化为可被门限检测的幅度信息；最后针对陷波滤波效果、系统误码性能以及频带利用率进行了仿真与分析。仿真表明，时相调制系统中采用陷波滤波技术，不仅可以完成对输入数字信息的有效恢复，而且使系统传输性能保持很好，并能有效提高频带利用率。