Design And Implementation Of Underwater Video Acoustic Transmission System

The underwater video transmission has been a very active subject in high-speedunderwater acoustic communication field.In recent years, with the development ofcomputer and multimedia communication technology, the application of embedded systemhave advanced in all fields, which the underwater video transmission embedded system basedon DSP has become the focus of research.The TMS320DM642(hereinafter referred to as DM642) chip from TI company is ahigh-performance video processing chip. With its rich resources on-chip and good ability ofsignal processing, DM642is extensively applied to video signal processing. Based on thetechnology of OFDM and DSP,this paper design a communication system to transmitunderwater video, which has a core processor of DM642for video processing and use CPLDto match the timing and control the logic. The processed signals can be transmitted to thehost computer by the network transmission, or converted into analog signals for display byvideo encoder chip. The system has the characteristics of low cost, small size, excellentperformance and so on.Firstly, this paper discusses the feasibility of underwater video transmission, simulatesthe entire video transmission system, and determines the parameters of the system which isbased on the simulation results. And then according to the structural characteristics of theDM642chip and the design requirements of system, this paper completes the hardwaredesign of DSP-based underwater video transmission system. In the hardware design part, thedesign of hardware circuit of power module, memory module, signal acquisition module,video display module and communication module is introduced in detail, while the designprocess of the frame memory address generator based on CPLD is described detailedly, andthe key technologies of the design process of PCB is studied. In the software design part, thispaper introduces the design of program and drive which is based on the framework ofembedded real-time operating system of DSP/BIOS and TI’s RF5. Then it emphasizes theimplementation and optimization of h.264algorithm in DM642and the realization of mainmodules of ODFM.At the end of the paper, it illustrates the results of joint debugging of communicationsystem, according to the lack of system design and personal experience, some improvementideas are given.