跳频信号时频分析的一种新方法

A Novel Method of Time-frequency Analysis for Frequency Hopping Signal

利用魏格纳-威尔变换等非线性时频分析方法,对跳频信号进行时频分析存在交叉项干扰的问题。为提高对跳频信号进行时频分析的准确度,提出一种新的时频分析方法。对跳频信号首先进行奇异点的检测,根据奇异点的位置将跳频信号划分为不同的单载频信号,然后利用非线性时频分析方法对单载频信号进行逐个处理,最后将得到的多个单载频信号的时频关系按跳频规律进行组合,进而得到完整的跳频信号时频关系。仿真验证了新方法可有效抑制交叉项,准确可行。

Nonlinear time-frequency analysis methods such as Wigner-Ville transform can＇t resolve the cross-term jam problem of frequency hopping signals. This paper proposes a novel method to improve the performance of time-frequency analysis about the frequency hopping signal. Firstly, we divide the frequency hopping signals into several single different carrier frequency signals based on singular locations after detecting singularity points. Secondly, each single carrier frequency signal is analyzed by the nonlinear time-frequency analysis method. Finally, we assemble the time-frequency relationships among the single carrier frequency signals based on frequency hopping rule, therefore, the integrated time-frequency relationship of the frequency hopping signals can be obtained. Computer simulation shows that the proposed method can restrain the cross-term jam effectively.