基于中国余数定理的跳频信号相时延估计方法

跳频信号每跳带宽窄且多跳间积累困难，利用传统方法对其时延估计精度都很低。针对该问题，该文充分挖掘跳频信号宽跳带的潜能，建立了多频点相时延估计模型，把时延估计问题转化为整周模糊求解问题；然后在解模糊过程中引入中国余数定理，针对非合作场景中模数无法选择的问题，提出一种基于虚拟频点的干涉相位外推方法，构造出鲁棒中国余数定理的适用条件；最后采用闭式鲁棒中国余数定理解算整周模糊，得到高精度的相时延。该方法具有精度高、运算量小、不依赖于信道衰落特性的优点。仿真结果验证了所提模型及方法的有效性和正确性。

A Phase Delay Estimation Algorithm of Frequency Hopping Signal Based on Chinese Reminder Theorem

The bandwidth of each hop in frequency hopping signal is very narrow, and the accumulating between multiple hop is difficult, thus the accuracy of time delay estimation for frequency hopping is low. To deal with the problem, the potential of wide band hopping of frequency hopping signal is fully exploited. A multi-frequency phase delay estimation model is established, and the problem of time delay estimation is transformed into ambiguity resolution. Then, Chinese Remainder Theorem (CRT) is used to solve the ambiguity, but in the non-cooperation scene the module can not be chosen easily, thus an extrapolation method for interferometric phase based on virtual frequency is proposed to relax the constraint of module selection. Finally, the closed-form Robust Chinese Remainder Theorem (RCRT) is used to solve the ambiguity, and the phase delay is obtained with high accuracy. Compared with the conventional algorithm, the proposed algorithm has the advantages of high precision, low computation complexity and independence on the propagation characteristics of the channel. The simulation results verify the validity and correctness of the proposed model and algorithm.