相参短脉冲辐射源双站TDOA/FDOA直接定位算法

当目标辐射源脉冲信号持续时间较短时， FDOA引起的信号脉内相位变化很小，几乎可以忽略，无法实现TDOA和FDOA联合定位。针对上述问题，通过对相参辐射源信号脉冲间相位补偿，提出了一种利用信号的TDOA和FDOA信息的最大似然直接定位算法。考虑采用运动双站对固定目标辐射源定位情况，以确定性未知信号为模型，推导了高斯白噪声背景下相参脉冲信号联合定位的最大似然估计算法，仿真分析验证了该算法可以利用双站实现对短脉冲相参辐射源的TDOA/FDOA定位。此外，还推导了相参脉冲联合定位的CRLB，表明所提算法在常规信噪比下定位精度可以达到CRLB。 

Direct Positioning Maximum Likelihood Estimator Using Bistatic Stations TDOA and FDOA for Coherent short-pulse Emitter

The intra-pulse phase change caused by FDOA is so little, even omitted due to extremely short duration of radar pulses, that we can’t realize the joint location using TDOA and FDOA of signals received by bistatic stations. Aimed at the above-mentioned problem, a multi-pulse coherent accumulation algorithm of direct position determination using TDOA and FDOA is proposed by phase compensation among pulses. Consider the case that there are only two moving receivers used to estimate the position of emitter. Through establishing coherent signal model of short pulses which is deterministic but unknown, the maximum likelihood estimator is derived by taking the DPD approach under additive Gaussian white noise environment. In this wok, we also derive a signal-specific CRLB of DPD, modeling the signal as a deterministic unknown. Simulation results show that the accuracy of proposed method is close to CRLB in high signal-to-noise ratio (SNR). Simulation results show that location accuracy of the proposed algorithm can achieve the CRLB under the normal signal-to-noise ratio(SNR) and the performance is also very well in low SNR.