Design Of Optical Fiber Strain Sensing Demodulation System Based On DSP

The signal demodulation system of Fabry-Perot optical fiber sensor's of the white light interference principle is designed according to needed in this article. It has the good stability, strong resolution, cost low and good resistance to interference. It may carry on the production, has the very widespread prospect.The type and the principle of light interference optical fiber strain sensor's have carried on the analysis in this article. Introduce digital signal processing's present situation, and design the optical fiber sensor's multi-channel electrical signal demodulation system which is based on the DSP signal processor and the micro electron signal processing. The circuit design of this system mainly aims at the process of the optical fiber strain sensors optical signal into electrical signal, namely the design starts from output's electrical signal of the linear CCD to carry on. In this design forward channel include signal pretreatment part, the multi-channel signaling switches transform the module, the ADS805 gathering module, the buffer module, the level switch module and so on; The digital signal apparatus module contains DSP2812, the clock circuit, the power circuit and its auxiliary circuit and so on; Backward channel include warning module, memory module, connection module and LCD display module and so on. The multi-channel change-over switches is used in the system, can thus carry on the gathering analysis to the multi-channel signals; the comparator module is used, causes the signal processor only to process the effective element signal, raise the data processing speed; Use the DSP2812 processor to enable the system to have the quicker handling ability to realize the signal real-time processing and the demonstration.In the article shows the master routine flow chart according to the signal processing process, design A/D gathering program flow diagram according to the gathering signal's process, as well as carries on the communications system flow chart of the serial port correspondence and so on. And according to the DSP2812 signal processing algorithm, design a maximum value law to discover most strong point of the luminous intensity, and then obtain the outside strain capacity size.The electric circuit schematic diagram the design development and the simulation are carried on by using protel99se then produces the PCB graph of it to carry on the wiring. The software programming uses the C language to carry on.