摘要
在机载平台上,采用相距较远的两个天线测量辐射源信号的相位差,这些相位差测量整周模糊。传统的解整周模糊方法通过增加天线元来实现。本文将整周模糊数建模为系统状态变量的一个分量,然后分析了该系统状态的可观测条件,并与只测角无源定位系统可观测条件比较。分析结果表明:只测角系统可观测性的充分必要条件只是该系统可观测性的必要条件;当可观测条件满足时,该系统可以通过积累相位差测量估计出整周模糊数,从而能实现高精度的无源定位。
With a pair of antennas spaced apart, an airborne passive location system measures phase differences of emitting signals. Regarded as cyclic ambiguities, the moduli of the measurements traditionally are resolved by adding more antenna elements. This paper models the cyclic ambiguity as a component of the system state, of which the observability is analyzed and compared to that of the bear- ings-only passive location system. It is shown that the necessary and sufficient observability condition for the bearings-only passive location system is only the necessary observability condition for the passive location system with phase difference measurements, and that when the system state is observable, the cyclic ambiguities can be estimated by accumulating the phase difference measurements, thereby making the observer able to locate the emitter with high-precision.
