ON-BOARD SWITCHING TECHNOLOGY

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On board switching technology has been talked about and experimented in the past 30 years. The technology was intended for replacing satellite transponders commonly used on GEO satellites today. On-board switching technology allows direct communications among all user terminals (UT) under the coverage of one single satellite. This approach eliminates double hopping between any UTs in today's VSAT network using DVB/TDMA technology, which only supports star topology. That's huge bandwidth savings. However, for GEO at 36,000 Km orbit with tens of thousands of UTs under each satellite, it is hard to image how many modems are needed to be installed on one single satellite. This is the reason on-board switching technology has not been deployed on GEO satellites. On-board switching requires many, lots of modems and at least one high-speed router on board each satellite. It has been challenging for the industry, but not until Mantaray launched On Board Switching capability using its proprietary PSMA technology. Mantaray's PSMA technology features single board implementation for On-Board Switching deployment over LEO satellites. Each single PSMA board comes with minimum 104 modems (expandable to multiple hundreds) and one high speed router. The modems are all modern SCPC and MCPC devices that connects to hundreds of UT terminals on ground. It also has separate channels dedicated for ISL connections to facilitate LEO to multi-LEO's broadband connections. The embedded router in each PSMA board routes traffic packets from modem to modem and to ISLS, and vice versa. The router calculates in real time the shortest path based on not only network segments, but also physical distance from the source to destination.