Design and implementation of a radar waveform playback system for real-time digital signal processing test

This paper designs a radar waveform playback system used for real-time digital signal processing test. The system reads radar waveform data stored in a disk array, and transfers it to a real-time signal processing system. The timing sequence and speed of the waveform data played back is the same as when radar in target tracking operation. The system comprises a disk array server, which is used for data recording and storing, and two FPGA (Field Programming Gate Array) fiber boards, which is used for data playback and transmission. Firstly, data transmission from the server to the fiber boards is realized by DMA (Direct Memory Access) in PCI Express protocol. And the DMA control flow for the system is proposed. Secondly, the method of timing control according to radar working mode is proposed. Accurate timing control can be realized by FPGA. Thirdly, the problem of asynchronous data transmission between two fiber boards caused by incoherent clock is solved. We propose two synchronization methods based on software and hardware respectively, and analyze the application conditions of each method. This paper offers a reference for the implementation of waveform playback in a radar system, and can be helpful for the function test of the realtime digital signal processing system.