Patent ID: 6985458

Claim:
A method of balancing a load in transmission on a plurality of channels between a satellite and a plurality of users to take into account variations in signal degradation, the method comprising: transmitting signals between the satellite and the users in a series of time-division multiplex (TDM) subchannels which collectively make up a frame, each frame corresponding to one of the channels, each channel having a plurality of the subchannels, each subchannel constituting a link with a signal, each subchannel having a different code rate than the other of the plurality of the subchannels, and, at a given time, each TDM subchannel having an associated packet length, code rate, and symbol rate; determining the signal degradation associated with each TDM subchannel being used for a corresponding one of the users, the signal degradation for a given TDM subchannel being dependent on a corresponding path between a satellite and the corresponding one of the users; changing assignment of the users to the channels based on the signal degradations with users grouped together on a channel when their signal degradations are within a degradation range corresponding to the channel, there being a signal degradation range corresponding to each of the channels at a given time, each user being assigned to a corresponding subchannel within that user's corresponding channel, there being different symbol rates on the channels; and dropping any user TDM downlink subchannel having a signal degradation greater than a limit and reassigning the packet length(s) associated with any dropped downlink to TDM subchannels corresponding to still active downlinks; said signals being transmitted from the satellite to the users via downlink paths, each using a downlink TDM subchannel.