US 8,805,275 B2 · Robust beam switch scheduling

Abstract

Systems and methods are described for robust scheduling of beam switching patterns in satellite communications systems. Embodiments operate in context of a hub-spoke satellite communications architecture having a number of gateway terminals servicing large numbers of user terminals over a number of spot beams. The satellite includes switching subsystems that distribute capacity to the user beams from multiple of the gateway terminals in a shared manner according to a beam group switching pattern. The beam group switching pattern is robustly formulated to continue distributing capacity during gateway outages (e.g., when one or two gateway terminals are temporarily non-operational due to rain fade, equipment failure, etc.). For example, the beam group switching pattern can be formulated to minimize worst-case degradation of capacity across user beams, to prioritize certain beams or beam groups, etc.

Claims30

Dependent claims

A satellite communications system for robust sharing of gateway resources between a plurality of gateway terminals and a plurality of user terminals over a plurality of fixed location beams, the system comprising:

a satellite comprising:
input subsystems configured to receive forward-link communications from a plurality of gateway terminals via a plurality of input beams;
output subsystems configured to transmit the forward-link communications to a plurality of user terminals via a plurality of output beams;
and
a beam group switching subsystem associated with a plurality of the input subsystems and at least one of the plurality of output subsystems and configured, according to a beam group switching pattern, to sequentially couple the associated input subsystems with the at least one associated output subsystem in such a way that distributes capacity to each associated output subsystem in a shared manner from at least two of the associated input subsystems.

2 more elements

a satellite comprising:
input subsystems configured to receive return-link communications from a plurality of user terminals via a plurality of input beams;
output subsystems configured to transmit the return-link communications to a plurality of gateway terminals via a plurality of output beams;
and
a beam group switching subsystem associated with at least one of the input subsystems and a plurality of output subsystems and configured, according to a beam group switching pattern, to sequentially couple the associated at least one input subsystem with the associated output subsystems in such a way that return-link capacity of each of at least a subset of the input beams is serviced in a shared manner by at least two of the associated output subsystems.

2 more elements

A method for robust sharing of gateway resources between a plurality of gateway terminals and a plurality of user terminals over a plurality of fixed location beams, the method comprising:

receiving, in a first time slot, a first portion of a forward-link communication destined for a target user terminal, the first portion received by a first input subsystem of a satellite from a first gateway terminal via a first input gateway beam;
receiving, in a second time slot, a second portion of the forward-link communication by a second input subsystem of the satellite from a second gateway terminal via a second input gateway beam;
coupling, by a beam group switching subsystem of a satellite in the first time slot according to a beam group switching pattern, the first input subsystem with an output subsystem of the satellite associated with one of a plurality of beam groups that supports a plurality of output beams including an output user beam that services the target user terminal, the beam group switching pattern defining which of a plurality of input subsystems are coupled with which of a plurality of output subsystems in each of a plurality of time slots;
coupling the second input subsystem with the output subsystem by the beam group switching subsystem in the second time slot according to the beam group switching pattern;
transmitting the first portion of the forward-link communication to the target user terminal in the first time slot via the output subsystem and the output user beam;
and
transmitting the second portion of the forward-link communication to the target user terminal in the second time slot via the output subsystem and the output user beam.

4 more elements

Dependencies are inferred from the claim text.

Robust beam switch scheduling

Life of this patent

Robust beam switch scheduling

Life of this patent

Abstract

Claims30