Study On Video Transmit System Base On FPGA

Along with the rapid development of information science and technology nowadays, people's demand on supervisory system is getting higher and higher, the real-time monitoring system is also entering in every field of our daily life gradually, the recently thriving wireless communication technology, the low price wireless facilities, universalization of the Internet, all of which have accelerated the development of wireless network, thus monitoring systems with high performance, high real-time property and strong reliability have been applicated widely, and are becoming more and more popularized. Therefore it is becoming more and more important for rapidly transmission and accuracy of image information, in this article we has studied coding and sending process of the monitoring video on the basement of what stated above.Spread-spectrum communication technology is the mainstream of modern communication system, it is applicated widely in every communication fields due to its merits, and the image coding and transmitting process stated in this thesis bases on the spread-spectrum communication technology in mobile communication, firstly, study the basic technical principle, technical index of spread-spectrum communication and some typical codes applicated in direct-sequence spread-spectrum system, secondly, introduce the Hardware Description Language VHDL which is used for realize the system above and the FPGA chip used for Hardware Support, because of the exist of high performance FPGA chip, the real-time transmission of image code with so much information can be realized. Finally in this article, the key work is the realization of the process of channel coding and spectrum spreading on FPGA chip with high performance, the FPGA used in the thesis is EPM7512AEQI208-10 of ALTERA company in USA, the whole process of imagine coding mainly realized the corresponding processes on serial video stream, mainly includes: the by-pass of I and Q, the Differential Code, the Gray-Code and the Spread-Spectrum modulation, in the end, completed the FPGA procedure of the intermediate frequency transmitting unit. The superiority of system performance has been proved through modulation and multi-time examinations, it has achieved a higher level than domestic similar products.