MF-TDMA satellite link power control

1. A method for determining attenuation settings across carriers in a return link from a user terminal to a gateway terminal via a satellite in a satellite communications system, the method comprising:

determining a first attenuation setting for a first carrier of the carriers in the return link, the first attenuation setting based at least in part on a first signal quality metric value of a first message previously sent on the first carrier;

determining a second attenuation setting for a second carrier of the carriers in the return link, the second attenuation setting based at least in part on a second signal quality metric value of a second message previously sent on the second carrier, the first attenuation setting being different than the second attenuation setting, the first carrier being different than the second carrier, and the carriers in the return link including the first carrier, the second carrier, and additional carriers; and

computing a respective attenuation setting for each of the additional carriers in the return link not including the first carrier and the second carrier based at least in part on the first attenuation setting and the second attenuation setting.

2. The method of claim 1 further comprising transmitting a burst transmission from the user terminal to the gateway terminal, the burst transmission transmitted on a third carrier of the carriers in the return link using a third attenuation setting, the third attenuation setting being one of the respective attenuation settings computed based on the first attenuation setting and the second attenuation setting.

3. The method of claim 1 wherein the first message comprises a plurality of first periodic management messages and wherein the first attenuation setting is determined based on an average of the first signal quality metric values of the plurality of first periodic management messages, and the second message comprises a plurality of second periodic management messages and wherein the second attenuation setting is determined based on an average of the second signal quality metric values of the plurality of second periodic management messages.

4. The method of claim 1 wherein the first signal quality metric value is based on a signal power estimate of the first message sent on the first carrier and the second signal quality metric value is based on a signal power estimate of the second message sent on the second carrier.

5. The method of claim 1 wherein the first signal quality metric value is based on a first signal-to-noise ratio of the first carrier and the second signal quality metric value is based on a second signal-to-noise ratio of second first carrier.

6. The method of claim 1 wherein the first attenuation setting is based on one or more measurements performed at the user terminal.

7. The method of claim 1 wherein the first attenuation setting is based on one or more measurements performed at the gateway terminal.

8. A user terminal in a satellite communications system, comprising:

a measuring module configured to measure a signal characteristic of one or more first messages sent from the user terminal at a first transmission frequency and to measure a signal characteristic of one or more second messages sent from the user terminal at a second transmission frequency;

a first determining module configured to determine a gain at the first transmission frequency and a gain at the second transmission frequency based at least in part on the signal characteristic of the one or more first messages and the signal characteristic of the one or more second messages; and

a second determining module configured to determine an attenuation setting of the user terminal at a third transmission frequency based at least in part on the gain at the first transmission frequency and the gain at the second transmission frequency, wherein the first transmission frequency, the second transmission frequency, and the third transmission frequency are each different frequencies.

9. The user terminal of claim 8 wherein the signal characteristic of the one or more first messages is a signal power of the one or more first messages, and the signal characteristic of the one or more second messages is a signal power of the one or more second messages.

10. The user terminal of claim 8 wherein the signal characteristic of the one or more first messages is measured by an outdoor unit of the user terminal, and the signal characteristic of the one or more second messages is measured by the outdoor unit of the user terminal.

11. The user terminal of claim 8 further comprising a transmitting module configured to transmit a third message at the third transmission frequency using the attenuation setting of the user terminal determined by the second determining module.