基于分级波束形成的三维声纳系统设计

Design of 3D sonar system based on multistage beamforming

针对三维声纳波束形成海量运算造成硬件系统复杂难以实现的问题,设计了基于分级波束形成的三维声纳系统。系统基于大规模(48×48)换能器接收基阵,采用分布式现场可编程门阵列(FPGA)结构实现两级波束形成,所需计算量相比传统波束形成减少九成。该算法经Matlab仿真验证了其合理性,系统样机经水下试验证明:在水平50°垂直50°覆盖角的观测范围内,实现角度分辨率达到0.39°,距离分辨率达到2cm的三维成像。

Aiming at problems that beamforming massive computing of 3D sonar makes complex hardware system which is difficult to realize, design 3D sonar system based on multistage beamforming. Based on large scale of transducer receiving arrays, the system utilizes distributed FPGA structure to achieve two stage beamforming, reduce 90 % of computing amount, compared with traditional beamforming. Rationality of the algorithm is verified by Matlab simulation. Tests underwater demonstrate that, within range of 50°horizontal and vertical coverage angle, 3D sonar system is able to form 3D image with angular resolution of 0.39° and distance resolution of 2 cm.