Hardware-sotfware Implemented Of Small-Platform Imaging Sonar Based On SOPC

In recent years, with the rapid increase of underwater acoustic imaging technologies,high-performance and small-platform imaging sonar was widely used in underwaterexploration missions due to its merits, such as small size, low power-consumption and highprecision.In the background of system design for small-platform imaging sonar, this thesisdiscussed the3-D acoustic imaging algorithm based on L-shape array,, then analysed theconventional beamforming technologies, fixed on the phase-shift beamforming method as thebasis for imaging algorithm. Built up3-D acoustic imaging model, and used matlab softwareto verify the imaging model. Through analysed the simulation result of matlab software,confirmed the enforceability of imaging algorithm, built up the theory foundation fordesigned and implemented of system.Based on the3-D acoustic imaging algorithm for L-shape array, and considered theperformance requirements of small-platform imaging sonar system, this thesis used theSOPC(System On a Programmable Chip) technology to found the system construction for theimaging sonar, took advantage of Avalon system interconnect fabric and hardware-softwareco-design technology to build a high-performance SOPC embedded system. The main worksof construction of SOPC embedded system contain:(1)constructed a synchronization controlsystem mainly consists of Nios II processor and UARTs.(2)Builded a real-time transfer andstore system mainly consists of SDRAM interface control logic module and PCI9054localbus to Avalon-MM bus convert logic module.(3)Implemented and optimated the orthogonaltransformation algorithm logic, beamforming algorithm logic and2-D image-constructionalgorithm logic.(4)Used the Matlab and Modelsim software setted up a co-simulationplatform to verify the function and interface logic designs.Finally, connected the entire imaging sonar system and tested the hardware circuits, andthen carried out the imaging experiments in the pool. The results of imaging experiments fullyproved the correctness of system development schemes and the3-D acoustic imagingalgorithm based on L-shape array.