三坐标PRC-CW雷达信号处理机设计与实现研究

【作者】 陆扬明；

【导师】 是湘全；

【作者基本信息】 南京理工大学 ， 信号与信息处理， 2010， 硕士

【摘要】 伪码调相连续波(PRC-CW)雷达是相位编码雷达的一种,它是用伪随机码对载频信号进行调相后发射的连续波雷达。该雷达常用于近程探测,随着雷达技术的发展,近程探测雷达不仅要获取目标的速度、距离信息,还要获取目标的角度信息,实现三坐标雷达的精确定位功能。本课题研究的三坐标伪码调相连续波雷达是应用于靶场炮弹脱靶量的指示,该系统可以精确的监测炮弹的三坐标参数,从而估计出炮弹的落点,实现脱靶量的指示功能。本文就是针对伪码调相连续波雷达如何实现目标三坐标参数的获取而展开的。伪随机码具有优良的自相关特性,这是雷达实现精确测距的主要依据；同时伪码调相雷达具有连续波雷达良好的测速性能,因此可以精确获取目标的速度参数；对于目标角度参数的获取,主要是基于比幅法测角原理实现的。三坐标伪码调相连续波雷达的信号处理系统是利用Xilinx公司的Virtex-4 FPGA实现的,该信号处理系统由AD采集电路和FPGA电路两部分组成。AD采集电路将模拟相关器的输出信号转换为数字信号,FPGA电路则对数字信号进行信号处理,从而得出目标的速度、距离、角度信息。该系统的数字信号处理部分包括FFT处理、恒虚警处理(CFAR)、对数运算等关键技术。本文最后介绍了信号处理的硬件电路,主要包括：信号调理电路、采样电路、FPGA信号处理电路,并对信号调理电路、采样电路进行了测试以及FPGA电路的下载调试。更多还原

【Abstract】 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.更多还原