Research And Design Of The Video Module In Digital Optical Transceiver Based On CPLD

Optical communications systems are mainly used in high-bandwidth requirements, the high demand for real-time communication system, In this paper, that is, the study background is the highway video surveillance. Before the signal processing is generally in the form of electrical signals. To complete the transmission of the optical signal transmission medium, Then it must convert electrical signals to optical signal. It requires an equipment which can convert electrical signals to optical signal, called optical transceiver. The optical transceiver which transmit the digital signal is called digital optical transceiver.With the development of optical communication technology, Digital optical transceiver has become an essential of the digital optical communication. and also it is an essential to complete the communication system which the communication medium is the light. To complete the digital signal processing of the image and voice signal transmission, Then complete the reuse processing of these digital signal, so that multiple low-speed digital signals into high-speed signal all the way, And convert this signals into optical signals. In light signal receiver will restore the optical signal to electrical signal, reduction of high-speed signal decomposition of the original multi-channel low-speed signals, finally then restore the data signal to image, voice signals. Digital optical transmission is widely useful in the area of video surveillance application. Because of the unprecedented advantages of the video surveillance, has a broad scope of application, so usually popular concerning. Video surveillance is always intuitive, convenient and accurate, rich and so on. As people's awareness of video surveillance continuously updated, the increasing amount of information transmission, The transmission capacity of optical transmission which use for video surveillance develops from the initial one-way transmission to the development of multi-channel transmission. Multi-channel video and other signals in the single optical fiber transmission to achieve significant savings for long-distance transmission line resources, and reduce the costs effectively.I am responsible for the project in the video modules for debugging and development, Projects for the circuit board system compatible with four video lines, two audio lines and two data lines. Paper uses the circuit board which is made in the project as former board, the optical transmission which is based on the CPLD is divide in two parts called transmitter and receiver. A video module for example, The transmitter of the former board which is made in the project including video signal processing module and signal system module. The function of the video processing module of the optical transmitter is to process the PAL video signal which is collected with the CCD camera and convert into 8 bit quarrel digital signal. The video resume module of the optical receiver is the inverse process of this process, is to convert the 8bit parallel into the PAL video signal. In the optical transmitter, the system reuse module is divided in two parts, in the former board, the function of the first part is complete the 4 lines 8bit parallel digital video signals and the signals of other modules first reuse process via the programming in the CPLD, and convert the video signals which are many and low-frequency into high-frequency 16bit parallel signals. The function of the second reuse process is to convert the 16bit parallel low-speed signals into serial high–speed signals, and then they can be transmitted in the Fibre Channel. The function of the first auti-reuse process is anti-reuse the serial high-speed signals into 16bit parallel data, the function of the second anti-reuse process is to transmit the 16bit parallel data to the CLPD, and then complete the second anti-reuse process. And then anti-reuse the 16bit parallel signals into 8bit digital video signals, And then enlarge the signals in two steps. To connect the output which is already enlarged to the video surveillance monitors.This paper will focus on the design of the digital reuse module of the transmit board and the receive board, and complete the first reuse process and the second anti-reuse process in the receiver. In TDM digital communication system, High-speed system can be pool with thousands of low-speed signals, the essence of digital multiplexing is to complete the TDM of the multi-channel digital signal. Let the different roads signals to occupy different time slots, and divide the signals based on the different time slots. It called tap. Tap is the anti-process of the reuse process. Either the positive signals or the reverse signals has to be done the process in two steps. The design of the first reuse and the second anti-reuse is completed in the CPLD. The design of the second reuse and the first anti-reuse is completed in the HDMP1032A/1034A.In the first section of this paper, the development history of the fibre transmission and digital optical transmitter and the development status of the digital optical transmitter has been introduced. In the second section we introduced system design features of the program and system performance, Introduced a string signal transmission and the characteristics and the basic color video signal theory, and then generally introduced the design plan of de system and the index of the design plan. Chapter III is for the hardware circuit design. The hardware which are used in the system is described in detail. The simulation results of the program which comes from the CPLD in the system transmitter and receiver. And made an 16 lines system patulous plan based on the theory of the former board in the project. Experiment results are given in the fifth section.