一种改进的CORDIC实时生成加权系数方法  

An improved CORDIC method for generating weighting coefficients in real-time

作　　者：杜俊桥 夏伟杰[1] 孙璟 DU Junqiao;XIA Weijie;SUN Jing(College of Electronic and Information Engineering,Nanjing University of Aeronautics&Astronautics,Nanjing 210016,Jiangsu,China)

机构地区：[1]南京航空航天大学电子信息工程学院,江苏南京210016

出　　处：《声学技术》2023年第5期661-668,共8页Technical Acoustics

摘　　要：基于现场可编程门阵列实现多波束声呐频域波束形成算法时,通常需要使用坐标旋转数字计算(Coordinate Rotation Digital Computer,CORDIC)方法实时生成加权系数,但波束数较多且为宽带信号时会消耗大量硬件资源。文章提出一种改进的基于CORDIC方法实时生成加权系数的方法。通过频点复用处理,多个波束组可共用同一个CORDIC IP核依次实时生成加权系数,降低了87.5%的CORDIC IP核资源消耗;通过引入二维乒乓、用后即抛思想,对存储加权系数的随机存取存储器(Random Access Memory,RAM)基于波束和频点复用进行乒乓处理,可降低97.9%的RAM系数存储空间占用。该改进方法通过多维度复用处理,占用少量RAM存储空间来节省大量CORDIC IP核资源,均衡了RAM和CORDIC IP核资源的消耗,具有很好的工程应用价值。For the field programmable gate array(FPGA)based beamforming algorithm of multi-beam sonar in frequency domain,the coordinate rotation digital computer(CORDIC)algorithm is usually required to generate the weighted coefficient in real time,but for large number of beams and broadband signal,a lot of hardware resources would be consumed.An improved real-time weighted coefficient generation method based on CORDIC is proposed in this paper.By frequency point multiplexing,multiple beam banks can share the same CORDIC IP core to generate weighted coefficients in real time,which reduces CORDIC resource consumption by 87.5%.By introducing the idea of two-dimensional ping-pong and throw after use,the ping-pong processing of the weighted coefficient cache RAM based on beam and frequency point multiplexing can reduce the occupancy of RAM storage space by 95.3%.This improved method saves a lot of CORDIC resources by occupying a small amount of RAM storage space and balances the consumption of RAM and CORDIC resources,and has good engineering application value.

关 键 词：CORDIC IP核现场可编程门阵列 加权系数 实时 复用 硬件资源 

分 类 号：TN929.3[电子电信—通信与信息系统]