Enhancing direction-finding accuracy for shortwave fixed stations

In this paper, we improve the direction finding accuracy for shortwave fixed stations located in imperfect environment. A correction method of direction finding data is proposed based on least square algorithm. Firstly, we establish the mathematical model of the relationship between real azimuthal angles and errors according to the statistical features of direction finding data. Then we design model parameters and estimate revised values with regard to azimuthal angles. When processing different frequency signals transmitted from the same location, we optimize the weights to derive an optimal azimuthal angle in each direction. The experimental results show that root-mean-square error decreases 0.7386 degree after correction, and our method improves the direction finding accuracy significantly without changing the original direction finding devices.