Wavelength Dimensioning of Optical Transport Networks Over Nongeosychronous Satellite Constellations

Massive data traffic demand leads to the proposal of satellite constellation networks providing broadband communications for users. The key technology to satisfy the high capacity requirement of future communications between satellites is the optical intersatellite link (ISL). Wavelength-routed optical transport networks over nongeosychronous satellite constellations (WROTNS) show the most promising future, since the networking by means of wavelength division multiplexing (WDM) ISLs with wavelength routing can not only efficiently utilize the optical amplifier bandwidth on board the satellite but also simplify routing decisions and minimize processing delays on board. In the paper we consider that the physical ISL topologies of the WROTNS are the arbitrarily connected networks. Based on the first satellite constellation with the proposal to include WDM ISLs and wavelength routing, its time-variant optical ISL topology is analyzed, and then a large number of randomly generated connected networks with distinct topologies are investigated to estimate the bounds of wavelength requirements. The results show that wavelength requirements of the WROTNS are determined by percentage of active terminals, maximum admissible ISLs hops, and the number of optical ISL terminals on board, and they are also time dependent. The topologically regular WROTNS are studied as well. These works are helpful to evaluate the design of constellation networking.