Waveform design based on double frequency modulation slope for distributed space-borne radar system

In order to obtain diversity gain and achieve good resolution performance, distributed space-borne radar system requires transmitting orthogonal waveforms with low Doppler sensitivity.The relation between parameters of double frequency slope (DFS) waveform is deduced after studying the performance of autocorrelation, range resolution, cross-correlation and Doppler sensitivity.Then, a waveform parameters designing method of DFS waveform is proposed according to the requirement of distributed space-borne radar system, and the DFS waveform with good orthogonal performance and low Doppler sensitivity is designed.It is indicated that on the condition of the pulsewidth unchanged, the orthogonal performance of DFS waveforms gradually enhanced with the increase of the differences of frequency slope between sub-signals, and the low Doppler sensitivity performance can be reached by increasing the signal bandwidth and decreasing the differences of frequency slope.The simulation results show that the DFS waveform designed by the proposed method can meet the requirement of distributed spaceborne radar system well.