The Impact Analysis Of Pre-processors Performance On Signal Detecting

Underwater Acoustic Positioning System (UAPS) is widely used in naval testing site and plays a significant role in testing and evaluating the performance of underwater carrier vehicle. Firstly, this thesis introduces the foreign research status of underwater acoustic positioning technology, represents some typical positioning products from ultra-short baseline systems to long baseline system, and simultaneously summarizes several domestic positioning systems which have been applied in marine testing site.In an UAPS, pre-processor is the primal entryway for signal processing of the whole receiving system, just as eyes and ears for a man, whose performance will have a crucial effect on subsequent digital signal processing. With the high-speed development of modern digital signal processors, the structure of pre-processors has changed a lot, tending to integration and miniaturization.Secondly, this thesis analyzes the structure of preprocessors in four typical sets of positioning systems used in naval testing site, develops a general structure suit for the wide-band vector signals and cooperative sound source, and explores their different characteristics. Also analyzed in detail are the differences between actual and theoretical pre-processor as well as the reason.Finally, attention of this thesis is paid to the means of signal processing for Notch filters and a single acoustic vector hydrophone. The different performance of these pre-processors is analyzed profoundly, and the impact on these two methods of signal processing is also discussed when the performance of the pre-processor is changed.