Real-time Analysis Of Spectrum And Research On Sorting Technique For Wideband Radar Signal

Digital frequency measurement and sorting technique is one of the key technologies of electronic reconnaissance systems.Along with the complexity of the battlefield and variety of radar system,the task that estimating carrier frequency of radar signal in real time,selecting the same kind of radiation signals from the mixed pulses and acquire accurate parameters of the radiation has become an emergency.Based on the application background of radar reconnaissance receiver,the paper researches deeply into the key technology for digital frequency measurement and sorting technique of radar signal.It finally accomplish the module design of rapid frequency measurement and signal sorting on an FPGA platform.Firstly,the paper gives a detailed description on research status and developing trend of digital frequency measurement and signal sorting technique.Then,it selects an algorithm that is suitable for implementation on hardware,having low requirements for SNR and meeting realtime and high precision requirements.The third part of the paper makes a systematic research on sorting technique of radar signals.It first describes the importance of sorting technique in the electronic reconnaissance system,and then introduces a variety of signal sorting parameters.It studies on pre-sorting techniques which uses multi-parameter.,and then shows several sorting algorithm based on PRI and their implementation steps while summarizing their advantages.Finally the paper focuses on PRI transform algorithm and its improved algorithm,and makes a simulation on the algorithm's performance by Matlab.It then makes a conclusion for this part.The last part of the paper realizes a frequency measurement and signal sorting system on FPGA.It first gives the design thought of 512-point FFT in pipeline structure for each channel and 8-channel parallel processing while making a detailed description on functional requirements and implementation of each module.The simulation results show that it only takes 2.1 ?s to finish the 4096 data caching and FFT operation at 300 MHz for the processor,which meets the accuracy requirements.The paper also makes a detailed introduction for designing the sorting system.Microblaze is selected as the core to build hardware platform,making user logic and processor interconnect by AXI bus and using interrupts and DMA mechanisms to transmit pulse information from FIFO to DDR3 in high speed.Finally,the paper selects RF and PW as the presorting parameters for joint sorting,using improved PRI transform method for the main sorting,and gives detailed processes and final sorting results.