由于被动雷达中广泛应用的测角方法应用于宽带信号测向时存在着各种问题,将互谱法应用于被动雷达宽带信号测向。针对互谱法测向中相位模糊与测角精度存在的矛盾,提出用两频率点的频率差和对应的互谱相位差值的关系来解相位模糊的频率相位差值法,突破了互谱法中阵元间距不大于信号最小波长一半的限制,有效地保证了测角精度。最后对相位差值进行修正,解决相位跳变问题,用两个阵元即可实现宽带信号测向。仿真表明了该算法的有效性。
In wide-band passive radar systems,the most widely used algorithms are flawed,so the cross-spectra algorithm is used to get rid of their weaknesses.Considering the contradiction between precision and phase ambiguity,a method named frequency-phase difference algorithm is presented.The relation between two-frequency difference and corresponding phase difference is used to solve phase ambiguity,and the constrain that the length of the baseline must be less than the shortest half-wavelength of the signal is not needed,thus the ac-curacy of direction finding is effectively improved.At last,the phase difference is modified to overcome the problem produced by phase jump,making the wide-band direction finding with only two antennae achievable. Simulation results show the effectiveness of the algorithm.