航天器微弱DS/FH测控信号长时间相干累积捕获技术OA

To address the problem that chip range walk exceeds half a chip period due to large Doppler shifts and long-time integration in high-dynamic scenarios,which degrades coherent integration gain and detection performance,this paper proposes a long-time coherent integration acquisition technology for weak DS/FH(Direct Sequence/Fre-quency Hopping)TT&C(Telemetry,Tracking,and Command)signals of spacecraft.Based on the traditional half-chip sliding cross-correlation matrix,a sliding-window matrix to be corrected is constructed first.Then,an extraction matrix is designed using 0/1 logic operations,and the sliding cross-correlation correction matrix is obtained by extract-ing from the sliding-window matrix to be corrected.Subsequently,chip range walk correction is completed by combin-ing fractional delay compensation.Notably,the proposed technology maintains a computational complexity compa-rable to that of existing fast coherent integration acquisition technologies,while significantly improving frequency hop-ping coherent integration gain and detection performance.Verified by comprehensive simulation analyses under vari-ous conditions,the proposed method can effectively resolve the bottlenecks of coherent integration gain and detection performance in high-dynamic,large Doppler,and long-time integration scenarios.It not only provides a reliable techni-cal solution for capturing weak DS/FH TT&C signals but also offers important theoretical guidance and practical value for the engineering implementation of related spacecraft telemetry and tracking systems.