Coordinates Registration and Error Analysis based on Spherical Model for OTH Radar

Different from the conventional radars, the over-the-horizon radar (OTHR) faces complicated nonlinear coordinates transform due to electromagnetic wave propagation and reflection in ionospheres. A significant problem is the phenomenon of multi-path propagation. Considering the problem, the coordinates registration algorithm spherical measurement model is derived in detail in this paper. Noticeably, a new transforming expression of apparent azimuth and an integrated form of transforming expressions from measurement vector to ground state vector are proposed and then simulations are made to verify the correctness of the algorithms. The simulations show that the transforming expression of apparent azimuth proposed in this paper is also correct. Besides it, the transforming error rates of slant range, Doppler and apparent azimuth of the model are given respectively. Then the quantitative analysis of error rate is also given. It can draw a conclusion that the coordinate registration algorithm of spherical measurement model is correct. Further more, when there exists ionospheric height error, the transforming error analysis of range and bearing are given