Research And Programme Of Digital Optical Terminal For Monitoring Based On CPLD

There is no doubt that with the rapid development of optical fiber communication, optical termination optical fiber transmission system is important equipment, and fiber optic transmission equipment is a signal to the optical signal, the optical signal to electrical signal converter. In previous transmission, such as the simulation of various FM, AM, phase modulation fiber optic transmission equipment in the market take up a considerable proportion of analog fiber optic transmission equipment is the base-band video, audio, and data signals in the modulation of a carrier frequency, the optical transmitter for optical fiber transmission, and then through the other end of the optical receiver demodulates and resume to the appropriate base band video, audio and data signals.However, with the development of its own shortcomings and the wonderful proving of digital fiber optic transmission that decide equipment and rapidly expanding applications of the various occasion endless digital fiber optic transmission equipment. Compared with analog fiber optic transmission equipment, digital fiber optic transmission equipment is to be the image and voice transmission to digital signal processing, then these figures signal multiplexing processing, multi-channel low-speed digital signal all the way into high-speed signals, and This signals into optical signals. This requires the receiving end optical signals into electrical signals reduction, reduction of the high-speed signal decomposition of the original multi-channel low-speed signals, then the final reduction of these data signals into images, voice signals. Resulting in the video surveillance, fiber optic transmission equipment is completed by a single road to the development of multi-channel.In this paper, digital fiber optic transmission equipment to support transmission of video, audio and data signals, the CPLD is based on the number of fiber optic transmission equipment to support two-way video and two-way audio and two-way bi-directional data transmission, mainly divided into transmitter and receiver of the two copies, which also audio, video, data module, is also available as a core module of the complex connections.Audio from the pickup in the collection is the analog audio signal to the first level of care through the conversion, the output signal from the pickup and audio analog-digital conversion chip input matching. And the need for digital video signal, the analog video signal and amplitude in the time frame of the shaft are discrete processing and transmission. And the use of a serial data transmission, serial communications, that is in the order by a certain amount of time of transmission. The use of a computer data signal line data in a data signal transmission line by bit, every data occupy a fixed length of time. Interface standards introduced in RS-232C, RS-422 and RS-485 communication standard three. In response to the complex at the same time the realization of the modules using a serial de-serialize SN65LV1023/SN65LV1224 realized, and describes the characteristics of the chip. In the digital and digital-to-analog converter module introduced in the AD9203 and AD9280, AD9750 and AD9708 four converters, and the choice of a concrete realizationThe research design of this digital fiber optic transmission equipment to achieve the main road two video surveillance, and for other occasions in the application of digital fiber optic transmission equipment and digital fiber optic transmission equipment can be in this on the basis of the practical requirements of different function expansion to make it applicable to various applications.