Tunable Fiber Fabry-Perot Filter Control System Based On FPGA

With substantial growth on people’s demand for information, the Dense WavelengthDivision Multiplexing(DWDM) technology has been widely used. As a key component ofDWDM system, the tunable optical filter can filter out light with one specific wavelengthin a certain range. A lot of attentions on the application of the tunable fiber Fabry-Perotfilter has been paid, due to its characteristics of low bandwidth, low insert loss, widetuning range and rapid tuning speed. However, some applications require its controller towork fast and precisely.This thesis proposes a high accuracy and fast speed control circuit based on FiledProgrammable Gate Array (FPGA). It achieves the serial communication between FPGAand computer. The design of this controller consists of both hardware and software parts.For the hardware design, we select an Altera FPGA as the core controller. Peripheralcircuits include serial port communication circuits. In order to generate and display signal（DC/Triangle/Sine）, the controller also includesAnalog/Digital(A/D)、Digital/Analog(D/A)、waveform generation chips.For the software design, we use embedded soft-core to achieve the communicationbetween FPGA and computer. Following the serial communication required, we configurethe soft core to get the top-level circuit in the SOPC Builder environment. Subsequently,we use C language to complete the system’s software design and debugging in NIOS ⅡIDE environment. And on the computer we use the Laboratory Virtual InstrumentEngineering Workbench (LabVIEW) software development platform to obtain a easyman-machine interface.In the end, debugging and experiment results show its high precision and fast speedof the FPGA based controller system for the tunable fiber Fabry-Perot filter, and furtherconfirm the feasibility of our design.