Research Of Wireless Video Traffic In The System Of Urban Sewage Monitoring And Realization The Key Technology

In China, a high sewage interception of the drainage network in cities and other regions has played an active role in improving urban water environment. However, such problems influencing water environment as mixed rain and sewage access, water overflow as well as network leakage have attracted an increasing attention. Therefore, it is necessary to conduct research in such key techniques as urban drainage network construction, transformation, as well as operation and control.With the further improvement of automation in urban sewage disposal, high quality wireless video communication has become the new requirement for urban sewage treatment system. In view of this, the paper carried out research in above requirement as well as each part of wireless video communication, and put forward a effective and useful wireless video communication program. At present, the paper completed work of the verified version of the wireless communication system and the verification of part of the key technology in video compression. However, because of the limitation of the time and personal professional, there is still much work to do before the program is fully completed.This program adopted the technology of hardware video codec and software wireless system based on FPGA, out of which the video codec adopted AVS_M. AVS_M which is of China's independent intellectual property rights, is relatively simple and suited to wireless transmission. In this program, the wireless transmission system used the 16 QAM to realize the wireless video transmission through 5.8G free channel. At present, the paper completed the work of the verified version of the wireless communication system and the verification of part of the key technology in video compression, including: (1) the research work of image disposal and AVS_M codec technology in PLA format image such as video capture, part of the key technology in AVS-M and VGA display. In the aspect of video information processing, the paper adopted PLA standard camera as the hardware for image capture, decoded video data formats to CCIR656 by the chip of ADV7181 video decoder on the DE2 development board, and then carried out AVS-M video compression by FPGA. The 16QAM modulation of Software Defined Radio (SDR) was selected to achieve video transmission by analysis and comparison of a variety of modulation and demodulation techniques in wireless transmission. (2) IF transceiver system with the base-band rate based on Xilinx Spartan3 FPGA reaching 2 MHz and the transmission distance 10 meters. This system adopted 100M Ethernet to carry out communication between PC and FPGA. Modulation and demodulation of 16QAM was based on FPGA. Ethernet signal transmitted through DAC on AD9860 chips and its native DUC which can converse frequency to the IF 32 M, and received by AD9860 chip's native DDC and ADC. This program is about the capturing and compression of the digital camera's video signal and sending it by wireless. The receiver received the compressed video signals, then decoded the video signals and transmitted to PC. The experimental results showed practical efficiency of such programs.