Pulse Compression with Very Low Sidelobes in a Spaceborne Weather Radar

Pulse compression with very low sidelobes is one of challenges in the design of spaceborne weather radar. To detect the weak echoes of clouds occurring near the strong echoes of sea surface, sidelobe performance below -60 db is needed in the pulse compression system. Based on the traditional ways of pulse compression, double Kaiser Windows are applied here for sidelobe suppression and the Peak Sidelobe Level (PSL) can reach -75 db. To avoid power and SNR loss, the time domain Kaiser Window weighted on transmitter was replaced by the frequency domain window weighted on receiver equally. A real time signal processor and digital predistortion method based on successive overrelaxation (SOR) arithmetic is carried out. It can be used for verifying the arithmetic and modifying the nonlinear and noise character of the system.