| The purpose of the research is to simulate the radar echo signal in real-time, which is in agreement with the actual navigation radar operating-environment characteristic and provided for ARP7A&VTS systems.The mathematical model of radar target and operating-environment is presented. The model of radar target is composed of distance, bearing, speed, heading and amplitude of echo, fluctuation. The distance, bearing, speed and heading are defined by the method of vector. The radar echo amplitude is mainly determined on the radar cross section. The fluctuation of the radar echo is illustrated by the Swelling' model I. The mathematical model of the radar operating-environment is composed of sea-clutter, rain-clutter, thermal noise, false target and interference signal from another radar operating at the same band etc. The thermal noise is generally modeled as a white Gaussian noise (WGN). The sea-clutter and rain-clutter are modeled as a stable stochastic process with a certain amplitude distribution and a kind of power spectral type. A method has been proposed to make the stochastic sequence correlated by passing it into a low-pass filter, which is based on an estimation of spectrum. It has been realized to simulate the correlated radar clutter by applying the above method. In addition, another method has been given to simulate the false target, which is based on the two-dimensional FFT. The correctness and practicality of this method are proved by the simulation result.According to the mathematical model, some algorithms have been designed for simulating the radar echo data. The software of simulation has been realized with Visual C++, the function of which is to produce the radar echo data and create the simulated image of radar video in real-time. The multi-thread program technique and computer-image processing have been involved in the software. The results of simulation show the applicability and effectiveness of the mathematical model and the software.
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