Crosstalk analysis of the ring light-trail networks

Light-trails have been proposed as a solution for optical networking to provide support for emerging services such as video-on-demand, pseudo-wires, and data-centers. Crosstalk is one of the key factors to restrict the performance as well as the extensibility of the light-trail networks. In this paper, causes of crosstalk by imperfections of the main optical devices in the light-trail node are addressed including the different behaviors of the intraband crosstalk and interband crosstalk. A four-node light-trail network with ring topology is built, which supports 9 × 2.5 Gbps capacity for communication. In addition, crosstalk of optical service channel (OSC) and data channels are compared by changing the isolation depth of the main optical devices. Besides, the corresponding BER as well as eye diagram are also given. Both analytical and simulation results show that the crosstalk of light-trail networks can be improved by enhancing the isolation depth of demultiplexer, multiplexer and OSC add/drop unit. And the OSC channel is more vulnerable to the crosstalk than the data channels. Moreover, the larger part of crosstalk in OSC channel is interband crosstalk, while the larger part of crosstalk in data channels is intraband crosstalk.