基于OCVR混频器的中频数字接收机设计

为了解决高速数字接收机中混频数据处理能力有限的问题，设计了基于八分圆周矢量旋转（OCVR）的高速数字正交混频器.该混频器仅通过简单二进制补码运算器和移位加法器即可实现，且不需要进行迭代运算.分析比较了常规的基于ROM架构、基于直接坐标旋转数字计算机（CORDIC）架构以及基于OCVR架构的混频器，结果显示基于OCVR的混频器拥有更高的数据吞吐量、更低的硬件资源消耗以及混频噪声小等特点.根据OCVR特性设计了武汉电离层斜向返回探测系统（WIOBSS）的中频（IF）数字接收机，该系统可以获取实时的宽带扫频后向散射电离图.实验证明该系统的探测覆盖范围已经延伸至3000km

Design of IF digital receiver based on OCVR mixer

In order to improve the processing capability for the frequency mixing data in high-speed digital receiver,a high-speed digital quadrature mixer based on the octant circle vector rotation(OCVR) was designed.The developed mixer could be realized only with simple binary complement arithmetic unit and shift adder without iterative operation.The conventional mixers based on such architectures as ROM,direct coordinate rotation digital computer(CORDIC) and OCVR were analyzed and compared.The results show that the mixer based on OCVR has such characteristics as higher data throughput,lower hardware resource consumption and smaller mixing noise.The intermediate frequency(IF) digital receiver of Wuhan ionospheric oblique backscattering sounding system(WIOBSS) was designed according to the features of OCVR.The real-time wide-sweep backscattering ionogram could be obtained with the WIOBSS.The experimental results show that the detection area of the system has extended to 3 000 km.