软件抗距离模糊技术在异步水声跟踪定位中的应用分析

Feasibility of resolving range ambiguities by software in an asynchronous underwater acoustic tracking system

异步水声定位系统可在目标信号发射时刻未知时对目标跟踪定位,此时发射和接收时钟存在固定时差。对于基于时延测量的长基线异步定位系统,当信号传播时延大于脉冲重复周期时,就会出现距离模糊。本文提出了在异步水声跟踪定位系统中软件抗模糊的思想,探讨了一种利用目标参考位置抗模糊的算法。从异步定位模型出发,得出等价的抗模糊准则,依据准则推导了算法及相应的参考位置取值范围,分析并克服了固定时差对算法的影响。海试结果验证了算法的可行性和有效性。

Asynchronous acoustic positioning system can locate a target when signal＇s emitting time is unknown. In this case there is a stable time difference between the emitter＇s and the receiver＇s clocks. For long-baseline asynchronous positioning systems based on measure of time-delay, range ambiguities appear when pulse＇s propagating time is longer than its repetition period. In this article an idea of resolving range ambiguities in asynchronous acoustic positioning systems by software is presented and a method of resolving ambiguities by target＇s reference location is discussed. The equivalence rule is obtained in terms of the asynchronous positioning modal, and an algorithm of resolving ambiguities and its responding reference scope are derived, and the influence of time difference is analyzed and overcome as well. The proposed method was proved to be feasible and valid by sea trails.