The Single Frequency Satellite Network Concept: Multiple Beams for Unified Coverage

This paper investigates the concept of single frequency satellite networks (SFSNs), whereby multiple satellite beams that have no form of mutual phase coherence are unified through baseband signal processing to achieve uniform coverage across wide areas. We present a realistic application scenario and its link budget analysis, which allows to highlight the advantages with respect to a classic single beam approach. Our technique is based on the use of orthogonal frequency division multiplexing and on the creation of synthetic multipath at the gateway, realizing a form of delay diversity. The synthetic power delay profile is beam specific, and it is the key instrument that allows to avoid destructive interference amongst the signals transmitted from the multiple beams. The main benefit is that homogeneous coverage is guaranteed with a generic multi-beam antenna, that can be easily reconfigured according to traffic and service needs.