针对均匀阵列难以同时估计多个不同载频辐射源角度的问题，提出了基于最大似然估计的多载频辐射源角度估计算法.该算法首先通过推导均匀线阵截获多辐射源信号的最大似然函数及其梯度，利用最速下降法同时估计出不同载频多个辐射源的角度；然后为了解决多个载频信号角度估计中可能存在的相位模糊问题，提出利用格点算法计算与模糊相位距离最近的整数点，通过布谷鸟寻优算法估计整数点对应的模糊数，解出无模糊多辐射源角度.仿真结果表明：与传统算法相比，该算法在低信噪比、低采样数、多辐射源的条件下，均具有较好的角度估计和解模糊性能.
Aiming at the angle estimation problem of uniform linear array in multiple carrier frequencies radiation sources passive reconnaissance, the angle estimation algorithm based on maximum likelihood estimation for multiple radiation sources with different carrier frequencies was proposed. The algorithm was divided into two steps. First, by deriving the maximum likelihood function and the gradient of the multiple radiation source signals intercepted by the uniform linear array, the angles of the multiple radiation sources of different carrier frequencies were estimated simultaneously by using the steepest descent method. Second, in order to solve the problem of phase ambiguity in different carrier frequencies, the lattice algorithm was proposed to compute the nearest integer points to the fuzzy phase. The cuckoo optimization algorithm was proposed to estimate the fuzzy number corresponding to integer points. Unambiguous angles of multiple radiation sources were obtained. The simulation results show that the proposed algorithm has better performance in angle estimation and unwrapping phase ambiguity than the traditional algorithms in terms of low signal to noise ratio (SNR), low sampling number and multiple radiation sources.
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