Influence of interface reflection on positioning performance and restraining technology

Based on the positioning solving principle of synchronous underwater acoustic positioning system, the effect of error in time-delay estimation from a single sensor on positioning precision was analyzed. Based on the characters of underwater acoustic channel, the change law in the phase difference between direct sound and surface reflected sound was revealed when the target is in different location; the physical mechanism of interfacial reflection influence on positioning precision was inquired into; the signal processing logic of conventional signal detector was improved using the character of signal superimposition, which is expressed as the time-delay difference between times of trailing and forward edges in offset interference signal is equal to the length of the sending signal, to improve signal detection ability and time-delay estimation precision, reduce multi-path influence on chronometric precision and modify the systematic performance. The simulated results show that the method is effective.