The Generation Technique Of Pulse Compression Radar Signal Based On DDS

Under the background of developing a signal generator system on pulse compression radar, the paper focuses on the generation and implementation of two signals - Linear Frequency Modulation (LFM) signal and Non-Linear Frequency Modulation (NLFM) signal. First several methods of the generation of "S-type" NLFM signal are respectively analyzed. Comparing those important properties, the change regularity of "S-type" NLFM signal is presented. And then based on "Anti-S-type" NLFM signal generated by Hamming window, a new higher performance NLFM signal is proposed. Finally, the performance of the two signals in ambiguity function, pulse compression results, ways to reduce the sidelobe, and the reflection of Doppler frequency shift is compared. It shows in the experiment result that NLFM signal is better in the application of radar waveform.DSP control software and hardware of two signals are designed on DDS waveform generation technique. Then both LFM and NLFM signal are successfully generated in an AD9854 chip.