Design Of Wideband Monopulse Radar Receiver

Wideband radar detection and tracking can provide accurate information of the target and higher data rate, this technology has been widely concerned. The current radar in our country are using narrow band detection and tracking, since the problem of wideband angle measurements has not yet resolved. A wideband multi-channel receiving system is required to solve the problem of amplitude and phase compensation in wideband radar, thus achieving the wideband angle measurements.In this paper, the experimental system is carried out to verify the wideband detection and tracking technology. A multi-channel digital receiver technology is proposed to solve the problem of amplitude and phase compensation. Consequently, wideband signal processing and parameter estimation of the experimental system can be achived. The research focus on the design of multi-channel wideband receiver technology, including the following works:Firstly, wideband monopulse radar system is designed, the composition of radar system is mainly described. The principle of monopulse comparison angle measurements is introduced. In this section, the factors affecting the accuracy of the angle measurements is analyzed and a wideband multi-channel technology is proposed to solve the problem in the angle measurements. Then the wideband signal processing is studied.The stepped frequency signal processing is employed to achieve the synthetic wideband signal. Based on this method, a novel method called multi-subpulse process of instantaneous wideband signal is proposed. The wideband chirp signal is split up to several subpulses and then processed by the stepped frequency processing method. The design of multi-channel receive technology and frequency synthesis system is introduced in the end.Secondly, the design and implementation of the intermediate frequency acquisition and control system is introduced. Firstly, the data acquisition and control system is designed. Then the ADC signal preprocessing is introduced, which mainly includes digital down conversion, LINK transmission and other technologies. The wideband ADC technology is implemented by using the parallel acquisition method. Finally, the design and implementation of interface logic section is accomplished.The display and control software of the receiving system is designed and realized. The overall process of the control software is presented firstly. Then the software driver interface is described. Finally the design of human-computer interface software is carried out.Finally,the test of LINK communication between the data acquisition system and DSP signal processing system is completed. Based on the existing radar system, the antenna pattern is scanned in the field, the sum and difference antenna pattern is compared before and after compensated, indicating the antenna pattern after compensated is much more closer to the ideal situation. The closed- loop test is conducted to verify the four channel amplitude and phase compensation technology. The high resolution range profile of narrowband signal and stepped frequency signal are processed respectively. The results are analyzed to verify the wideband radar receiving system.