Research And Implementation Of Sonar Signal Processing Algorithm For Underwater Target Positioning

Pinger signal is a pulse signal with a narrow bandwidth and pulse width and a fixed repetition period.It is a common signal used to locate underwater cooperative targets.In this paper,a multi-core DSP chip is used as a signal processing hardware platform to design and implement a set of real-time signal processing software.This software has signal detection and delay estimation.,Frequency estimation and target bearing estimation functions.The thesis finally completed the debugging of real-time signal processing software,the joint tuning of the positioning system and the lake test of the positioning system.The real-time signal processing software designed and implemented in this thesis was fully verified and achieved the expected goals.First,the thesis conducts theoretical and simulation research on signal detection,delay estimation,frequency estimation,and azimuth estimation algorithms for Pinger signals,and analyzes the effects of conditions such as signal-to-noise ratio and different parameters of pulse signals on signal detection and parameter estimation performance.The robustness and engineering feasibility of the algorithm were investigated.Based on the simulation results and the computational efficiency requirements of the real-time platform,a signal processing scheme based on the non-coherent accumulation algorithm based on STFT,the FFT interpolation algorithm based on frequency difference correction,and the beam domain MUSIC azimuth estimation algorithm was developed.Secondly,based on the signal processing theory and simulation analysis,the paper designs and implements the signal processing software based on the core processing chip TMS320C6678 through algorithm transplantation.The software implements data sharing and multi-core multi-threaded parallel processing by configuring NDK network interfaces and IPC inter-core communication modules,and uses TI's underlying function library to complete cache cache consistency maintenance.Then tested the real-time processing time and memory usage of the whole set of real-time signal processing software.Finally,the paper carried out laboratory debugging and performance testing of the signal processing software,participated in the laboratory joint debugging of the entire positioning system,and the whole system lake test test.The real-time signal processing software designed and implemented in this paper was systematically and comprehensively tested.Verification and successful completion of the thesis research work.