Research On Surface Surveillance Technology Based On Radar Sensor Network

The range and azimuth resolution of traditional Surface Movement Radar(SMR) are usually improved by increasing the bandwidth and the antenna aperture respectively. However, it is of much more difficulty to have a further improvement on resolution with the method mentioned above, for the reason that the radar with large antenna aperture requires an exponential increase in its cost of antenna and servosystem. This thesis focused on a new concept of SMR system combined with Radar Sensor Network(RSN) and Doppler- Only measurements, which is based on CW radar and can locate multi-targets simultaneously. This technology provides SMR with both higher resolution, and cost efficiency. Author studies the method of processing multi-targets, method of numeric calculation, condition of the method and its performance.Aiming at the defect that Doppler-Only measurements needs the information of target’s moving direction to locate, the thesis studies the locating method of Doppler-Only RSN based on the least square estimation(LSE), signal model and positioning method included. This method could locate the target without knowing its moving direction. To reduce the calculation cost, a method of numeric calculation is proposed applying the theory of LSE nonlinear model optimization. By utilizing the improved method, the dimension of the problem decrease from 4 to 2.For the multi-targets problem, this thesis propose a method called link separation method to classify the information of multi-targets. Multi-targets location is possible by using the method. And some features of the method are studied. Besides, with the special distribution of radar sensors, an assistant method is proposed to further decrease the calculation cost.The thesis also studies the conditions and the performance of this technology. A concept called tolerance of least square estimation(TOLSE) is proposed to deduce the condition that guarantees an unbiased estimation results. The condition suggests some relationship between the parameters of radar system and its resolution. Performances were studied. Simulation results show that targets’ moving direction, the geometric factor and noise would be influential.