Design And Investigation Of Optical Modem Digital Signal Processor Based On CPLD

As an important component of Electrical Integrated Automation Device project, the Optical Modem Digital Signal Processor is introduced in the article. It is composed of Programmable Logic Device as its key part and Interface Converter as auxiliary circuit, and exchanges electrical signal between DSP and Digital Laser Transceiver to realize communication of fiber-optical differential current protection.The article first introduces the theory of fiber-optical differential current protection, the structure of communication system, the requirement of Digital Laser Transceiver input signal and the character of Digital Laser Transceiver input signal. And then presents the design of Optical Modem Digital Signal Processor. Second it shows the design of sub modules of Optical Modem Digital Signal Processor, such as electrical transmitter, all digital lock-loop and electrical receiver, and gives the simulating result for each sub modules. Third, it presents the result of synthesis and the function simulation result by writing test bench to test and verify the circuit. At last it discusses the design and realization of Interface Converter circuit connected with DSP.The simulation and experiment make it clear that the solution meets the requirement of the design and will be of important usage in communication system of fiber-optical differential current protection. The Optical Modem Digital Signal Processor is simple constructed, efficiency and easy to use, and also can be of extensive used.