Direction finding method and system based on radio frequency analog receiving system

The invention provides a direction finding method based on a radio frequency analog receiving system. The method comprises steps of obtaining the phase difference between each path of antenna and an adjacent antenna through a phase discriminator for an N-element uniform circular array antenna, and recording the phase difference as the phase difference of the phase discriminator; recording the phase difference of each phase discriminator as an initial phase difference when an incoming wave enters the circular array antenna at an elevation angle of 0 degree; constructing a plurality of phase discriminators corresponding to each phase discriminator; according to an elevation angle and an azimuth angle, k is the number of iterations, and calculating the theoretical phase difference of each phase discriminator; introducing a vector X and a direction vector G, and calculating an elevation angle and an azimuth angle of a two-dimensional incident angle of iteration times k+1 in combination with the constructed complex number, calculating the difference between the two-dimensional incident angle with the iteration frequency of k+1 and the iteration frequency of k, comparing the two-dimensional incident angle with a threshold value, and entering an output elevation angle and an azimuth angle when the two-dimensional incident angle is smaller than the threshold value, otherwise, adding 1to the value of k, and calculating the theoretical phase difference. The method is advantaged in that problems of logic judgment and other operations, phase ambiguity and unbalanced amplitude of an input signal of the phase discriminator are avoided, and direction finding precision is improved.