Design Of The Multi-sensor Integrated Optical Fiber Transmission System Based On FPGA

To achieve the sensor signal real-time transmission with high speed in the complex industrial field, this paper proposes a multi-sensor integrated optical fiber transmission system based on FPGA. System can be completed for analog signal and digital signal acquisition, and through the application of time division multiplexing technology to achieve the multi-channel sensor signal by single fiber optic transmission, Inside the FPGA logic unit scale expanding gradually, make it possible to have A single communication circuit board integrated multiple signal interface, in the hardware circuit design, system integration the RS232/RS485, SPI and other commonly used digital interface, as well as analog signal interface circuit was designed and made up of signal conditioning circuit and A/D converter, on the basis of software development, considering the signal transmission, real-time demand signal within the FPGA are conducted in the form of parallel data processing. The system electromagnetic compatibility strong, long transmission distance, good real-time performance, can meet the complex environment over long distances, scattered, multi-point measurement of sensor signal real-time transmission.System delivery module is divided into optical fiber and optical fiber receiving module two parts, middle through optical fiber connection, optical transmitter module for signal collecting and FPGA as the main structure, signal sampling interface to the data, input the FPGA in data processing, data processing mainly includes three parts, one is the digital signal encoding, CRC check for error detection optical receiving module,2it is to define the transmission data frames, convenient and at the receiving end judgment valid data to transmit data source sensor. Three is to encode data frames, avoid long even "0" or even "1", favorable to the long distance transmission of signals and the receiver to extract the synchronous clock. Data processing is completed by FPGA, and the FPGA also need to control interface circuit of signal collection work. Fiber delivery module will be after processing, the data collected through a single optical fiber transmission to optical fiber receiving module, the receiver before processing the data should be based on the current optical fiber transmission of data to the clock recovery, data processing of the clock as optical receiving module, when the synchronous clock recovery data decoding, data transmission solution of frame, etc, to pick up the valid data, and then to CRC checking, and received the CRC error detection coding value contrast. Transfer data through RS232interface when confirmed first place machine for display, to look at this time, the value of each sensor acquisition.In this paper, the design of sensor interfaces directly to the light high speed, high integration, transmission system, using FPGA inside can be to the advantage of parallel processing of data, greatly improving the system of data processing speed, integrated analog signal and digital signal acquisition interface at the same time, make the system has high integration, flexible application, easy to transform, strong anti-jamming capability, etc.