Onboard Image Coding And Transmission System

As a new kind of equipment, battlefield image scout projectile shows itself by itsoutstanding capability and special function. Now armies of many countries lay emphasison battlefield image scout projectile and study deeply in this field. The main task of thepaper is to design a kind of image compression and transmission system for battlefieldimage scout projectile.At first, the characteristic of compressing on-board image was analyzed and the theoryof wavelet compression was introduced in the article. Then, the scheme of the hardwareand software that the video compression and wireless transmission system makes use ofwas expounded in detail. The precise acquisition of the video signals was first fulfilledthrough the SAA7111 video acquisition chip (made by Philips Co.). I~2C-BUS interfacingdesign of SAA7111 was realized by McBSP. The difficulty of SAA7111's initialization wasovercome; Video signal was encode by ADV611 that used wavelet from Analog DeviceCo., together with TMS320VC5402 (made by TI Co.) providing the bin widthcomputation which will be used in real-time wavelet transformation in our system; TheCPLD was applied in the design of logic control and timing and high-speed hardwarecircuit of TMS320VC5402 extended RAM and Flash, which overcomes the difficulty thatthe data memorizes of DSP is not enough and can not store image; In the way of translation,it designs a wireless translation circuit based on nRF2401, SPI-BUS interfacing wasrealized by McBSP of DSP, it brought out the software flowing design of wirelesscommunication. At last, we summarized the experiences from the system design. To theshort of this system, we brought forward some new solutions to improve system'sperformance at the end of this paper.In the design, ADV611 chip acquired a good compression ratio of the system. Theonline programming feature of CPLD was fully developed to simplify the hardware of thesystem, to strengthen flexibility and lower the cost.