A satellite communication system for providing communications between user terminals and gateways constituted with m primary satellites. In one embodiment, n back up satellites are also provided. Further, each satellite, primary or back-up, is equipped to project N/m beams onto and across an area in a loosely-packed array manner. M of the m primary and n back-up satellites collectively create N beam spots to cover the area. Moreover, each sub-area is covered by a beam spot separated from another sub-area covered by another beam spot by one beam width. Each satellite is also equipped to facilitate communication over 1 of m band of frequencies on one beam. As a result, any of the m primary satellites may be efficiently replaced on demand by a selected one of the n back-up satellites. The gateways and user terminals are configured to communicate signals through or with both or either the primary and back-up satellites.