Parameter Estimation of Phase Code and Linear Frequency Modulation Combined Signal Based on Fractional Autocorrelation and Haar Wavelet Transform

This paper proposes a new method using fractional autocorrelation and the Haar wavelet transform to estimate the parameters of phase code and linear frequency modulation combined signal. The combined signal is transformed into a linear frequency modulation signal using square method and its chirp rate is estimated by fractional autocorrelation firstly. Then, the initial frequency is estimated through dechirp method or fractional Fourier transform. Finally, the parameter of base band phase code signal is estimated by the Haar wavelet transform. Simulation results show the new algorithm can work well under the condition of low SNR.