海底三维声学图像实时处理系统设计  

Marine 3-D sonar imaging real-time processing system design

作　　者：李志华[1,2] 李秋峦 

机构地区：[1]杭州师范大学信息科学与工程学院,浙江杭州311100 [2]浙江大学数字技术及仪器研究所,浙江杭州310027

出　　处：《海洋工程》2014年第4期124-130,共7页The Ocean Engineering

基　　金：国家自然科学基金资助项目(61001170)

摘　　要：结合多核CPU硬件PC平台,设计了一种海底三维声学图像实时处理系统,主要包括声学前端信号处理子系统、数据传输控制子系统和PC客户端图像处理系统三个部分。声学前端信号处理子系统统根据接收到的多路声学换能器信号,通过两级FPGA信号处理,采集多通道水声信号,进行实时电子聚焦波束形成。为了解决海量声学数据快速传输问题,数据传输控制子系统未采用传统用户空间TCP/IP传输机制,而是直接通过嵌入式PowerPC处理器在Linux内核态采用DMA通道进行声学数据转发,减少系统调用和数据拷贝开销,有效提高网络传输效率。针对海量声学数据实时处理需求,PC客户端图像处理系统通过对复杂、耗时的单帧重建和数据拼接算法模块根据声学数据点的角度范围进行等分分割,对每个子范围声纳数据采用多线程并行处理,均衡多个CPU核之间负载,实现高性能三维声学图像实时处理。通过室内水池和湖试实验,结果表明该系统能够实时高效地进行三维声学图像采集、传输与处理。Marine 3-D sonar imaging processing system including sonar front-end signal acquisition sub-system,data transmission and control sub-system as well as PC-client imaging processing software system is designed using a multi-core CPU PC hardware platform.3-D sonar front-end signal acquisition sub-system receives sonar signals by two-level FPGA signal processing,and forms electronic focus beam.In order to achieve rapid transmission of huge sonar data,3-D sonar data transmission and control sub-system transmits sonar data in the Linux kernel mode and DMA channel by embedded PowerPC processor,and improves the network transmission efficiency by reducing system call and data copy.Aiming at real-time imaging processing requirement,PC-client 3-D sonar imaging processing software system achieves highly efficient imaging processing in the time-consuming single frame reconstruction and mosaicing modules by multi-thread parallel structure and load balance of multi-core CPU.Experimental results in the indoor pool and outdoor lake show that the system efficiently achieves 3-D sonar data acquisition,transmission and processing.

关 键 词：三维声学 实时处理 图像重建 图像拼接 嵌入式系统 海底 水声探测 

分 类 号：TB566[交通运输工程—水声工程]