基于FPGA的超宽带数字波束形成技术

随着高速ADC和高性能FPGA芯片工艺技术的飞速发展,芯片的小型化和集成化促进了电子战系统瞬时覆盖带宽由几十兆赫兹上升到几百兆赫兹甚至到吉赫兹量级,属于超宽带范畴.为了获得更远的探测距离性能,具备同时对多个辐射源侦测的能力,需要瞬时形成多个数字波束对目标区域密集覆盖.针对宽带时域校准与合成处理资源占用多、形成波束少的缺...

Technique of UWB Digital Beam-Forming for FPGA

With the fast development of high-speed ADC and high-performance FPGA,miniaturization and system integration for chips make instantaneous bandwidth of electronic warfare system increased from tens of MHz to hundreds or even thousands of MHz,which can be classified to ultra-wideband category.Compared with traditional electronic reconnaissance system,in order to achieve detection/identification of multiple radiation sources,multiple digital beams need to be formed to cover target area.High-performance FPGA has abundant logic operations and storage resources on-chip,which is highly suitble for realization of multi-beamforming in array signal processing.In order to reduce the resource occupancy rate of wideband time-domain calibration and synthesis processing and form more beams,integer point shift and phase calibration filtering method are used to realize channel calibration,and integer point shift and fractional delay filter processing are adopted to reduce synthesis filter coefficients in FPGA.Through simulating the directivity of multiple equally-spaced tone signals within the instantaneous bandwidth,the consistency of each frequency direction of the wideband synthesis is verified by the generated beam pattern.A calibration and synthesis integrated frequency domain processing method with real-time processing and less resource occupancy is proposed,and realized by hardware in combination with the characteristics of the FPGA chip.Then the spectrum before and after the DBF is compared.And the combining gain can be verified.