Active Positioning System Channel Matching Strategy Research And Realization

This dissertation is based on an underwater target tracking system project. The measurement arrays composed of four acoustic buoys receive and detect the signals from targets, and sent the results to the central control and display unit by wireless.The central control and display unit computes and displays the track of the target.The system works in active mode.The theoretical and simulation analysis about acoustic signal processing in multi-path channel and the engineering software design are given in the dissertation.The main task of acoustic signal processing module is to receive and process acoustic signals from hydrophone, select valid distance and depth pulses, and estimate the parameters such as frequency, time delay and so on.According to the charaters of buoy signal processing, Notch filter and VIFD detector are combined for signal processing, do the detecting and estimating in the same time. And in accordance with multi-path channel where the specific environment the system works in, the resistable multi-path interference pulse search and selection algorithm is designed for improving the system's positioning precision.The theoretical simulations are made by Matlab.In the project design, the core content is the assembly language software design based on two serial connected TMS320VC5402 DSP chips.Through lab simulator test and lake trial, the underwater signal processing module is proved to be satisfied with the system's demand and is with high time delay precision and reliability.