A Fully Transparent Fiber-Optic Ring Architecture for WDM Networks

In this paper, we propose a fully transparent fiber-optic ring architecture for wavelength division multiplexed (WDM) networks. The physical topology of the proposed network is based on a single or multifiber ring. The nodes at the periphery of the network are connected onto the ring via a polarization-independent acoustically tunable optical filter (PIATOF). This device is used as a means for injecting the transmission of each node at a predefined wavelength onto the ring and at the same time as a means for accessing the transmission of the other nodes. Expressions are derived for the throughput of different network configurations. It is found that the basic single-fiber ring configuration can support a large number of users provided the availability of PIATOF device with low insertion loss. In the multifiber ring configuration, the number of users can be increased by increasing the number of fibers irrespective of the value of the insertion loss of the PIATOF device.