Design of a multichannel ring network with tunable laser diodes and fixed optical detectors

Abstract

A multichannel ring is designed. Each sublayer network is connected to the ring with an access node (AN), which can transmit data at every wavelength with a tunable laser diode. The data transmission speed at each wavelength is 1.25 Gbit/s. With eight wavelengths, a total bandwidth of 10 Gbit/s can be obtained. With a bandpass filter, the de- sired optical signal can be dropped down at the access node. On receiv- ing a data packet, the optical signal is split into two parts. One part is converted to an electrical signal and its destination address is extracted and verified. If the data packet belongs to the local subnetwork, it is received. Otherwise, it is retransmitted to the next access node with a selected wavelength. So pipelining data transmission can be achieved among different wavelengths. And this network is a multipipeline struc- ture. The data processing time is less than 300 ns, and all of the pro- cessing procedure is implemented via a field programmable gate array (FPGA). So the communication latency and communication overheads can be decreased. Meanwhile, the ring topology has good scalability. More wavelengths can be adopted for a large-scale network with more access nodes. © 2003 Society of Photo-Optical Instrumentation Engineers.