一种基于数字去斜体制的雷达宽窄带协同探测的软硬结合实现方法OA

With the gradual opening of low-altitude airspace,activities involving low,slow,and small(LSS)targets,represented by unmanned aerial vehicles(UAVs),general aviation aircraft,and large bird flocks,are becoming increas-ingly frequent.Characterized by low flight altitude,slow speed,and small radar cross section(RCS),LSS targets eas-ily merge with complex ground and meteorological clutter,often making traditional surveillance methods inadequate for efficient detection.To address this problem,this study proposes a hardware design scheme for wideband and narrow-band cooperative detection radar based on a digital dechirp architecture.Utilizing board-level hardware,including the ra-dio frequency system-on-chip(RFSoC),optical fiber transmission cards,and field-programmable gate arrays(FP-GAs),the system establishes a cooperative operating mode that combines wide-area broad search(using broad beams and long-time integration)with high-resolution fine detection(using narrow beams and wideband signals).Meanwhile,for the dechirp radar architecture,a multi-channel calibration method combining hardware and software is proposed.To address frequency-domain inconsistencies in the wideband signal channel response of the radar analog front-end,the method first performs time-domain envelope alignment for single-channel signals within the dechirp domain.This pro-cess maps beat-frequency signals corresponding to different echo ranges to a unified time-domain reference,enabling subsequent amplitude and phase equalization for each channel.Second,to address sub-sample-level time mismatch in the multi-channel receiving link caused by analog front-end inconsistencies,radio frequency data converter(RFDC)sampling characteristics,and system clock distribution,fractional delay filters are introduced at the RFSoC stage to achieve hardware-level calibration of signal frequency consistency after dechirping.Subsequently,residual amplitude and initial phase errors of multi-channel signals are finely compensated on the graphics processing unit(GPU),achiev-ing sub-sample-level multi-channel consistency calibration that meets the precision requirements of the wideband dechirp architecture.Digital hardware implementation is carried out for digital beamforming of dechirp wideband sig-nals.Finally,a complete system comprising the radar front-end,digital boards,optical fiber transmission cards,server display control,and GPU data processing modules is implemented.Experimental results show that the system provides wide-area staring capability in narrowband mode and achieves a range resolution of approximately 0.5 m in wideband mode,validating the engineering feasibility of the proposed cooperative detection scheme.