针对脉冲辐射源定位问题,提出了一种基于短时时差(TDOA)序列的多站无源定位新方法。首先建立了TDOA序列模型,然后推导了该方法定位误差的克拉美罗下限(CRLB),并提出了一种高效的解算方法——两步定位法(TSLM):第1步利用TDOA序列线性估计出TDOA及其变化率信息,第2步基于TDOA及其变化率信息进行定位。典型场景下的分析表明:在短时间内,两步定位法获得的辐射源位置估计略微有偏,但大体上定位误差可较好地逼近CRLB;此外,脉冲重复周期越小,短时TDOA序列对应的定位精度越高;观测站速度越大,相应的定位精度越高。
To localize the pulse emitter,this artucle presents a new multiple-observer passive localization method by means of the time difference of arrival(TDOA) sequence in a short observation period.Firstly,the mathematical model of the TDOA sequence is established,and then the Cramér-Rao lower bound(CRLB) of the localization method is deduced.Moreover,the article proposes a computationally efficient solution named the two-stage localization method(TSLM).In the first stage,the TDOA and its rate of change are linearly estimated using the TDOA sequence.In the second stage,the emitter position is obtained by the TDOA and its rate of change.Finally,the article analyses the localization performance in typical scenes.The result shows that the TSLM estimate is with small bias in a short observation period,but the location error approximately approaches the CRLB.Besides,the smaller the pulse repetition period(PRI) is,the better the localization performance of the short time TDOA sequence is.The more quickly the observers move,the better the localization performance is.