Abstract: In order to expand the capacities of WDM star networks and free them from the restriction caused by the limited number of wavelengths, a scheme of reusing wavelengths is proposed in this paper. According to the scheme, not only can the number of nodes be doubled, but also all the data wavelengths can be reused in the network and the throughput of the network doubled. With the same number of nodes, the delay of the network can be greatly reduced and the properties of the network effectively improved. Besides, through the network structure proposed is simple, and the scheme can be easy implemented in practice. In this paper, the network structure is introduced first. Next, the properties of reusing wavelengths in the network are analyzed. The required gain and output power of optical amplifier in the network are computed, Finally, the maximum number of available wavelengths and the maximum number of supportable nodes in the network are also computed.

Key words: star network, wavelength division multiplexing, network capacities, gains, wavelength reuse