低信噪比S模式基带信号到达时间估计联合算法  

Joint algorithm for time of arrival estimation of S-mode baseband signals with low SNR

作　　者：宫峰勋 第五瑶光 GONG Fengxun;DIWU Yaoguang(College of Electronic Information and Automation,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学电子信息与自动化学院,天津300300

出　　处：《北京航空航天大学学报》2025年第2期380-388,共9页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家重点研发计划(2018YFC0809500)。

摘　　要：为提高接收低信噪比(SNR)S模式基带信号时广域多点定位(WAM)精确度,提出基于非相干积累的到达时间(TOA)估计联合算法。依托二次监视雷达(SSR)波束扫描驻留时间内目标应答信号具有的相关特性,提出并建立前导四脉冲匹配滤波、非相干积累的低信噪比基带脉冲信号上升沿估计方法,有效提升-15~5 dB范围低信噪比S模式基带信号TOA估计精确度。蒙特卡罗仿真结果显示,在-15~5 dB范围内的低信噪比S模式基带信号通过联合算法估计TOA的均方根误差(RMSE)优于25 ns。对于非理想S模式基带脉冲信号,信噪比低至-15 dB时,经过5个脉冲非相干积累的联合算法的TOA估计精确度达到22.245 ns,远优于WAM要求。To improve the wide area multilateration(WAM)accuracy when receiving S-mode baseband signals with low signal-to-noise ratio(SNR),a joint time of arrival(TOA)estimation algorithm based on non-coherent integration was proposed.According to the correlation characteristics of target reply signals during the beam scanning dwell time of the secondary surveillance radar(SSR),a low SNR baseband pulse signal rising edge estimation method with a four-pulse matched filter and amplitude squared operation and accumulation was proposed,which effectively improved the TOA estimation accuracy of S-mode baseband signals with a low SNR ranging from−15 dB to 5 dB.The Monte Carlo simulation results show that the root mean square error(RMSE)of TOA estimation by using the joint algorithm is less than 25 ns for S-mode signals with a low SNR ranging from−15 dB to 5 dB.For non-ideal Smode baseband signals,when the SNR is as low as−15 dB,the TOA estimation accuracy of the joint algorithm after the non-coherent integration of five pulses can reach 22.245 ns,which is much better than the WAM requirement.

关 键 词：到达时间估计 低信噪比 匹配滤波器 非相干积累 广域多点定位 

分 类 号：TN911[电子电信—通信与信息系统]