Coordinate transformation for OTHR with target height

The complicated nonlinear coordinate transformation commonly used in the over the horizon radar (OTHR) is not accurate for ignorance of the target height. In this paper, a novel OTHR measurement model considering the target height is proposed, and the detailed coordinate transformation formula between radar coordinates and ground coordinates is deduced. The simulation results of state estimate with and without target height show that the measurement model considering the target height can greatly decrease the state estimate error. The proposed method can effectively reduce the system bias caused by coordinate transformation, so as to improve tracking accuracy.