主动询问机制的星载二次雷达系统关键技术OA

Spaceborne secondary surveillance radar(SSR)systems equipped with active interrogation capabilities are in high demand for future aviation safety surveillance.However,due to the lack of spaceborne-specific optimization in current SSR technical standards,two major technical bottlenecks have emerged:ground transponders struggle to receive spaceborne interrogation signals,and severe signal overlapping in the spaceborne environment complicates the decoding of reply information.To address the limited reception capability of ground transponders,a spaceborne high-gain phased array antenna design is proposed to support both SSR and Automatic Dependent Surveillance-Broadcast(ADS-B)applications.By employing circular polarization,an active two-dimensional array configuration,and weighted beamforming techniques,the design achieves an antenna aperture equivalent isotropically radiated power(EIRP)exceeding 59 dBW,significantly enhancing the coverage of spaceborne interrogation signals.To tackle the challenges of weak and overlapping signal processing,a signal processing scheme incorporating autocorrelation filtering,adaptive thresholding,and local pulse cross-correlation is proposed.Furthermore,a time-threshold-based amplitude-phase dealiasing algorithm is introduced to effectively improve weak signal detection performance and enable the separation and reconstruction of overlapping pulses.Simulation results demonstrate that under low signal-to-noise ratio conditions,both the false alarm rate and miss detection rate significantly outperform those of conventional methods.Additionally,with up to 500 targets within a single beam,the sliding-window decoding probability remains above 95%.