脉内跳频信号研究

RESEARCH ON FREQUENCY STEPPING SIGNAL

摘要: 以频率跳变方式逼近任意的信号频率调制规律是设计复杂信号的有效方法。本文研究了在声信号检测中应用这种“脉内跳频信号”的一些基本问题。
首先,本文对脉内跳频信号的检测模糊度函数作了计算和分析,说明了信号频率量化所引起的检测模糊度函数的量化效应。接着指出,为了消除信号相位起伏对检测性能的影响,脉内跳频信号适宜于用“检波后匹配处理器”实现“最佳”处理。这种信号处理器的检测响应函数已经导出,并通过分析和“全相干检测器”的性能作了对比。最后,本文给出了一个“数控跳频信号源”的原理方案。其中,信号的跳频规律由指令装置按预定的数码控制,并且便于同“检波后匹配处理器”直接配合而组成完整的信号检测系统。

Abstract: A digital-controlled Frequency Stepping (FS) signal generator is presented. By arranging a set of digit-codes, a variety of FS signals can be generated to approach arbitrary Frequency Modulation (FM) modes. The ambiguity function of FS signals has been derived and analysed in detail. An effective signal processor, Post-Detected Matching Processor (PDMP), is introduced to process the FS signal. The characteristic function deciding the detection performance of PDMP is obtained and the comparison with All Coherence Detector (ACD) has also been done.