Adaptive Fade Mitigation

A method comprising:

• transmitting, from a terminal to a hub, a utility transmission;
• storing at the terminal a forward channel reception level estimation corresponding to a time of transmitting the utility transmission;
• receiving at the terminal a reception level estimation corresponding to the utility transmission;
• associating at the terminal said reception level estimation with a transmission power level used for transmitting the corresponding utility transmission;
• determining at the terminal a change in return link conditions based on said reception level estimation;
• and
• setting at the terminal at least a transmission power level property of a further transmitted signal in accordance with said determined return link conditions, according to said stored forward channel reception level estimation corresponding to a time of transmitting the utility transmission, and according to a forward channel reception level estimation corresponding to a time of transmitting the further transmission, wherein the difference between said forward channel reception level estimations is used for determining a transmission margin over the transmission power level based on said determined return link conditions.

A method comprising:

• receiving, at a hub from a terminal, a utility transmission including transmission capability information;
• determining at the hub a reception level estimation for said utility transmission;
• determining at the hub a capability figure for the terminal based on a reception level estimation and on the transmission capability;
• determining at the hub capability fluctuations associated with the terminal based on consecutively determined capability information;
• determining at the hub a return link state corresponding to the determined capability fluctuations;
• and
• determining an allocation margin in accordance with the determined return link state, wherein a relatively low allocation margin is determined if the return link state corresponds to stable link conditions and a relatively higher allocation margin is determined if the return link state corresponds to less than stable link conditions.

A satellite communication system, the system comprising a hub and at least one terminal, the system is configured to:

• determine at the hub a forward link state and a return link state on a per terminal basis;
• determine at the hub a forward link allocation margin for the terminal corresponding to a forward link state determined for the terminal;
• determine at the hub a return link allocation margin for the terminal corresponding to a return link state determined for the terminal;
• select at the hub a MODCOD for transmitting towards the terminal in accordance with a forward allocation margin corresponding to the terminal;
• allocate at the hub return link resources to the terminal in accordance with a return link allocation margin corresponding to the terminal;
• determine at the terminal return link conditions and a degradation in forward channel reception level between a time of measuring return link conditions and a time of transmitting a further transmission;
• and
• set at the terminal a transmission power level property for a further transmission in accordance with said determined return link conditions and forward channel reception level degradation.