HARDWARE PRE-PROCESSING FOR DATA OF UNDERWATER MEASURING SYSTEM

Abstract

The synchro double pulse signal mode is freqently used in Short Base Line (SBL) underwater positioning system so as to obtain the information of both distance and depth of a target simultaneously. Howerer, this signal mode also brings about ranging indistinctness resulting in a shorter positioning distance much less than that limited by the period of the synchro signal. This paper presents a hardware distance gate date acquiring scheme. It puts the original data sent to the computer in order of “direct first pulse--depth information pulse (or first pulse reflected by water surface)•••- to guarantee the effective positioning distance of the system. It has the advantage of reducing the processing time of the computer thus ensuring the realtime functioning of the system.