存在载频误差下的多普勒频移定位算法

针对非合作环境下目标辐射源信号载频估计存在误差的问题，提出了一种基于多普勒频移的无源定位算法。该算法充分考虑目标辐射源信号载频估计误差的影响，推导了在存在载频估计误差下的克拉美罗界(Cramer-Rao lower bound，CRLB)，并将该算法与忽略载频估计误差的算法进行比较。仿真实验发现，在存在载频误差的情况下，即使对于CRLB的影响只是1.5 dB左右，但若在目标定位时忽略该影响因素，会导致定位精度急剧下降。当忽略载频估计误差的算法开始偏离CRLB时，该算法仍能达到CRLB，且当噪声增大近40 dB后，才开始偏离CRLB。证明该算法具有较强的鲁棒性，且定位精度较高。

Source Localization Using Doppler Frequency Shift with Erroneous Carrier Frequency

In the non-cooperative scenario where the carrier frequency is not known exactly, the source localization using Doppler frequency shift is investigated. By taking the erroneous carrier frequency into account, a source localization algorithm is proposed based on Doppler frequency shift. The Cramer-Rao lower bound (CRLB) with erroneous carrier frequency is derived firstly, and then the proposed source localization algorithm is compared with the one ignoring erroneous carrier frequency. By simulations, it is found that although the CRLB with erroneous carrier frequency is 1.5 dB worse than the one without erroneous carrier frequency, the performance of the source localization algorithm ignoring erroneous carrier frequency deteriorates sharply. When the source localization algorithm ignoring erroneous carrier frequency starts to deviate from the CRLB, the proposed source localization algorithm can still reach the CRLB. It is not until the noise increases by nearly 40 dB that the proposed source localization algorithm begins to deviate from the CRLB. This proves that the proposed source localization algorithm is more robust and accuracy.