Abstract—Considering the issue that the recognition of LFM signal, NLFM signal, FSK signal and PSK signal, a recognition method based on fractional Fourier transform (FRFT) is presented. This method is divided into two steps. Firstly, according to the envelope curve of fractional order domain, by judging if the curve peak corresponding fractional order is 1, we can divide these signals into two categories. Secondly, notice that the sharp and flat degree of the curve is different, so in this paper, the kurtosis of curve and the difference of peak are used to demonstrate the sharp and flat degree, by setting the kurtosis threshold and the difference of peak threshold to obtain the final recognition result. The simulation results show that the new method has better recognition ability under low signal-to-noise ratio.
 

Index Terms—modulated radar signal, recognition of modulation, FRFT, feature extraction, sharp and flat degree

Cite: Shengnan Mi, Xinzhuo Liu, and Zhiyu Qu, "Recognition of Radar Signal Modulation Based on Fractional Fourier Transform," International Journal of Signal Processing Systems, Vol. 5, No. 2, pp. 65-69, June 2017. doi: 10.18178/ijsps.5.2.65-69