Direct digital generation of ultra-wideband LFM signal and its compensation technology

The linear frequency modulated signal is widely used in radar systems, and two methods, which are DDS and DDWS, are mainly used to generate the baseband signal. This system adopts the DDWS method, based on FPGA parallel theory and high-speed DAC framework, to generate the broadband linear frequency signal with bandwidth of 500MHz. The principle of filter-based pre-distortion compensation presented in the paper is used for the amplitude and phase compensation of system, and the ration of the main lobe to the side lobe after pulse compression has a significant improvement. Detailed steps about the implementation are given in this paper.