Coordinate Prc-cw Radar Signal Processor Design And Implementation

PRC-CW (Pseudo random code continuous wave) radar is one of the phase-coded radars. It is a kind of CW radar which modulates the carrier's phase according to the pseudo random codes. This radar is usually used for short range detecting, with the development of radar technologies, it is requested to not only acquire the velocity and distance parameters of target, but also obtain the angle information of target, and then it can realize the function of exactly orientation of three-dimensional radar. In this paper, the three-dimensional PRC-CW radar is applied to the measurement of undershooting on shooting range, which can exactly acquire the three-dimensional parameters, and then estimate the point of fall of the cannonball, so it can realize the indication of undershooting. This paper mainly concentrates on how to obtain the three-dimensional parameters based on PRC-CW radar.Pseudo random code has good characteristic of self-correlation, which is the key of exactly detecting distance. Acquiring the velocity of target is due to the perfect velocity measurement of CW radar. And according to the theory of comparing amplitude, we can obtain the angle information. The digital signal processing system of PRC-CW radar is implemented by Xilinx's Virtex-4 FPGA, which includes both AD sampling circuit and FPGA signal processing circuit. On the one hand, AD sampling circuit converts the output signals of analog correlator into the digital signals, on the other hand, FPGA signal processing circuit acquires the distance, velocity and angle information through the signal processing. The whole system involves some key technologies, such as FFT processing, CFAR (Constant False Alarm Rate), logarithm operation and so on.Finally, this paper introduces the hardware circuit of signal processing, it includes the signal modulation circuit, sampling circuit and FPGA signal processing circuit. Furthermore, some testing and debugging are carried on the circuit boards.