Frequency Detection Algorithm for Frequency Diversity Signal Based on STFT

Frequency diversity signal is a kind of pulse signal with multiple frequency which has high anti-interference performance, and is commonly used in target detection, localization and radio communication by detecting the characteristics in the signal. This paper focus on detecting the frequency characteristic which has its distinct advantages compared with other characteristics. At present, time-frequncy analysis is the most commonly used method. Short-time Fourier transform (STFT) is one of them, however, it is not adaptive to the low SNR. Therefore, this paper makes improvement on the basis of traditionl STFT according to the problem and proposes an novel algorithm for extracting the frequency characteristic of frequency diversity signal. The algorithm combines STFT with the false alarm and detection probability, which can make full use of the information in frequency-domain. And the accuracy of detecting the frequency could reach 95% under-25dB.