Design And Implementation Of Optical Burst Transceivers For OBS

Optical Burst Switching (OBS) networks can fully utilize bandwidth resource of DWDM optical networks and meet the requirement of burst traffics. It is a perspective solution for IP over WDM. Optical burst mode transmission and receiving technology is the key technologies for OBS edge nodes. This dissertation focuses on research of OBS edge's burst transmission and receiving technology. A scheme of burst mode transceiver for OBS edge based on FPGA is proposed, where burst mode receiving is implemented by space over-sampling technology, and burst mode transmission is implemented through controlling the work state of laser driver circuit. A burst mode transmitting/receiving card for OBS based on the proposed scheme is designed and implemented, which includes burst mode data recovery, burst data transmitting control,data transmission, data reception and relative periphery circuit. The main contents of the dissertation are as follows:1. Analyzing carefully current optical burst transceiver's development situation and the special requirements of burst transceiver in OBS networks. A scheme of optical burst transceiver based on FPGA technology is proposed, which consists of hardware logic for PHY layer and periphery circuit. Then the design and implementation of data transmission module and data reception module for 100M Ethernet PHY in FPGA is given in detail.2. The principle of over-sampling technology for data recovery is described and analyzed. The data recovery based on over-sampling technology in FPGA is designed and implemented including data sampling, edge detecting, best sampling point choosing and recovered data output. The problem of path delay control of asynchronous input is resolved through manual placement for sampling register banks. A configurable shift register is designed to overcome the influence of random clock jitter on data recovery.3. The design and implementation of control logic circuit for burst transmission is completed, where burst transmission of optical signal is realized through controlling the work state of laser's driver circuit. Device choosing, schematic design, PCB's placement and route and the debug of the periphery circuit are completed.4. A test scheme for optical burst transceiver and related testbench is designed. The basic function and the performance of burst transceiver such as bit error rate and protocol compatibility is tested. The results shows that burst transceiver can work normally with bit error rate of 10^-8, which can meet requirement of communication system. It is also compatible with 802.3 Ethernet PHY.