A Flexible MSS Space Based Network (SBN) for Service Continuity and Evolution

LightSquared’s Next Generation system consists of two integrated networks: a Space Based Network (SBN), which includes the satellite segment and four gateways, and an Ancillary T errestrial Network (ATN) consisting of several ATCs in high density population centers. This paper focuses on the SBN system consisting of an advanced satellite design with a 22 –m L-Band reflector, feeder link gateways, and Ground Based Beam Former (GBBF) that interfaces to the ground network. The system is designed to create up to 1500 L-Band satellite spot beams (cells) using the beam former and L-Band antenna array to support future ATN. The SBN is flexible to be able to support LightSquared legacy network from its previous generation satellite systems (MSATs) that have used a small number of regional beams to provide MSS services. LightSquared took advantage of this system flexibility and backward compatibility to implement an eight beam network configuration, which provides coverage over the MSAT regions, and enabled the legacy MSS traffic to be transferred to the new satellite system. The system has been configured so that MSAT satellites and SkyTerra-1 provide full back-up to each other to support current customer traffic. The SBN provides capability to support satellite services for multiple beam scenarios and emerging business and/or emergency situations including public safety and disaster management. The system architecture and beam performance in support of LightSquared’s MSAT legacy services are presented in this paper.