Research On TOA Extraction And Evaluation Based On Differential Matched Filter

The estimated accuracy of time of arrival(TOA)of the preamble pulse signal directly affects the accuracy of the positioning system.In order to improve the positioning accuracy of the positioning system,based on the research of matched filter and differential matched filter,the problem of the magnitude and distribution of the output root mean square error of the pulse signal differential matched filter is mainly studied,and by comparing and evaluating the output root mean square error of the differential matched from the aspects of signal-to-noise ratio,sampling frequency,and number of pulses,the extracted and estimated accuracy of time of arrival of the preamble four-pulse differential matched filter is verified.The surveillance response signal is introduced,the format of the S mode pulse signal is emphasized.The detection and identification methods of the preamble pulse header are summarized,laying a solid foundation for the accurate extraction and estimation of the pulse signal TOA.Simultaneously,the S-mode signal is simulated,the preamble pulse signal is especially discretized to facilitate subsequent experiments.From the perspective of single pulse and multi-pulse,the size and distribution of the output root mean square error of the matched filter and differential matched filter of the preamble pulse signal are analyzed,and the accuracy of TOA extraction and estimation of pulse signals is evaluated.Based on the principle of matched filter and differential matched filter TOA extraction and estimation,a TOA extraction and estimation algorithm for the four-pulse preamble signal differential matched filter is proposed,which uses two-pulse and four-pulse signals through differential matched filter to improve the TOA extraction and estimation accuracy of the preamble pulse signal.The part analyzes the relationship between the TOA extraction and estimation accuracy of the ideal pulse signal differential matched filter and the sampling frequency,discussing the time structure relationship between non-ideal pulse signals,comparing and evaluating the TOA accuracy of the matched filter and the differential matched filter,and finally verifying the differential matched filter algorithm effectiveness.From the perspective of pulse number,signal-to-noise ratio,sampling frequency,complexity and TOA extraction and estimation position distribution,the root mean square error of the differential matched filter is compared and evaluated,and the TOA extraction and estimation accuracy of four-pulse signal of differential matched filter is better than that of single-pulse signal.The real-time data received by the ADS-B receiver set in the terminal area of Tianjin Airport and simulation data under the same conditions were used to verify the accuracy and stability of the TOA extraction and estimation of the four-pulse signal differential matched filter algorithm.