Transmission loss budget design of the optical star-shaped ring network

Abstract

One high-fidelity ring-type optical transmission network is the star-shaped ring network having a multi-port accessory in its hub. The present paper describes the transmission loss budget design for the star-shaped ring network that takes into account continuously received interference signals. Conventionally, the S/X value, which is the ratio of the main signal power to an interference signal power, has been used to evaluate the degree of interference. First, the factors responsible for determining this ratio are discussed and then a design chart is derived to correlate the S/X value with the level difference between the transmitter and the receiver for the network. Based on this design analysis, multiport optical accessors are fabricated; and measured results are presented. It is demonstrated that the star-shaped ring network with, desirable performance can be realized successfully. Finally, a method to lower the level difference between the transmitter and the receiver using multiwavelengths is proposed.