Adjusting transmission power under changing conditions

1. A communication system comprising:

a hub with uplink power control having a power control margin corresponding to a magnitude of a hub side uplink fade condition that can be overcome by the uplink power control;

a repeater; and

a remote,

the hub is configured to

evaluate a value of a first predetermined function at an arithmetic combination of (a) the power control margin of the hub, (b) a predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using a first signal under a clear sky condition, and (c) a measured carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to the repeater and back to the hub using the first signal,

determine an external condition to be a deep fade condition when a magnitude of the external condition is greater than a difference between the clear sky condition and an evaluated value of a second predetermined function at the power control margin of the hub, and

adjust a transmission power of the remote depending on the external condition determined to be the deep fade condition based on (i) the measured carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to the repeater and back to the hub using the first signal, (ii) a measured carrier-to-noise ratio CN Hubsignal2 of data transmitted from the remote to the hub via the repeater using a second signal, (iii) the predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using the first signal under the clear sky condition, (iv) a predetermined carrier-to-noise ratio CN HubTDMACS of data transmitted from a reference remote to the repeater and back to the hub using the second signal under the clear sky condition, and (v) the evaluated value of the first predetermined function based on the power control margin of the hub.

2. The communication system of claim 1 , wherein the repeater is an earth orbit satellite.

3. The communication system of claim 1 , wherein the first signal is different from the second signal.

4. The communication system of claim 1 , wherein the first signal uses a continuous broadcast channel and the second signal uses Time Division Multiple Access (TDMA).

5. The communication system of claim 1 , the system further comprising:

another remote; and

the hub is further configured to adjust a transmission power of the another remote such that the remote and the another remote exchange data with each other under the external condition.

6. The communication system of claim 1 , wherein the external condition is one of clear sky, hub fade, hub fade and the hub has an uplink power control (UPC) unit, deep hub fade and the hub has the UPC unit, remote fade, hub fade and remote fade, hub fade and the hub has UPC unit and remote fade, and deep hub fade and the hub has UPC unit and remote fade.

7. The communication system of claim 1 , wherein the hub is configured to determine that the external condition is no fade at the hub and no fade at the remote when the hub determines that CN Hubsignal1 is equal to CN HubSCPCCS and CN Hubsignal2 is equal to CN HubTDMACS .

8. The communication system of claim 1 , wherein the hub is configured to determine that the external condition is hub fade and there is no uplink power control at the hub when the hub determines that a downlink component plus a noise component of the first signal is function only of CN Hubsignal1 and CN HubSCPCCS .

9. The communication system of claim 8 , wherein the hub is configured to maintain the transmission power of the remote when the hub fade condition is determined.

10. The communication system of claim 1 , wherein the hub is configured to determine that the external condition is hub fade and there is uplink power control (UPC) at the hub when the hub determines that a downlink component plus a noise component of the first signal is the difference between CN Hubsignal1 and CN HubSCPCCS .

11. The communication system of claim 10 , wherein the hub is configured to maintain the transmission power of the remote when the hub fade condition with UPC is determined.

12. The communication system of claim 1 , wherein the hub is configured to determine that the external condition is remote fade when the hub determines that a target value is different from CN Hubsignal2 .

13. The communication system of claim 12 , wherein the target value is the difference between CN HubTDMACS and a downlink component plus a noise component of the first signal.

14. The communication system claim 1 , wherein the hub determines the CN Hubsignal1 and CN Hubsignal2 periodically.

15. The communication system of claim 1 , wherein the communication system is a mesh network.

16. A communication apparatus that communicates with at least one remote via a repeater, comprising:

an uplink power controller having a power control margin corresponding to a magnitude of a hub side uplink fade condition that can be overcome by the uplink power controller; and

a control unit configured to

evaluate a value of a first predetermined function at an arithmetic combination of (a) the power control margin of the hub, (b) a predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using a first signal under a clear sky condition, and (c) a measured carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to the repeater and back to the hub using the first signal,

determine an external condition to be a deep fade condition when a magnitude of the external condition is greater than a difference between the clear sky condition and an evaluated value of a second predetermined function at the power control margin of the hub, and

adjust a transmission power of the at least one remote depending on the external condition determined to be the deep fade condition based on (i) the measured carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to the repeater and back to the hub using the first signal, (ii) a measured carrier-to-noise ratio CN Hubsignal2 of data transmitted from the remote to the hub via the repeater using a second signal, (iii) the predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using the first signal under the clear sky condition, (iv) a predetermined carrier-to-noise ratio CN HubTDMACS of data transmitted from a reference remote to the repeater and back to the hub using the second signal under the clear sky condition, and (v) the evaluated value of the first predetermined function based on the power control margin of the hub.

17. A non-transitory computer readable medium storing computer program instructions, which when executed by a computer, determine the computer to perform the following steps:

operating a hub with uplink power control having a power control margin corresponding to a magnitude of a hub side uplink fade condition that can be overcome by the uplink power control;

measuring a carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to a repeater and back to the hub using a first signal;

measuring a carrier-to-noise ratio CN Hubsignal2 of data transmitted from a remote to the hub via the repeater using a second signal;

storing a predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using the first signal under a clear sky condition;

storing a predetermined carrier-to-noise ratio CN HubTDMACS of data transmitted from the hub to the repeater and back to the hub using the second signal under the clear sky condition;

evaluating a value of a first predetermined function at an arithmetic combination of (a) the power control margin of the hub, (b) the predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using the first signal under the clear sky condition, and (c) a measured carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to the repeater and back to the hub using the first signal;

determining an external condition to be a deep fade condition when a magnitude of the external condition is greater than a difference between the clear sky condition and an evaluated value of a second predetermined function at the power control margin of the hub; and

adjusting a transmission power of the remote, depending on the external condition determined to be the deep fade condition, based on the CN Hubsignal1 , CN Hubsignal2 , CN HubSCPCCS , CN HubTDMACS , and the evaluated value of the first predetermined function based on the power control margin of the hub.

18. The non-transitory computer medium of claim 17 , further storing instructions for:

determining that the external condition is no fade at the hub and no fade at the remote when the hub determines that CN Hubsignal1 is equal to CN HubSCPCCS and CN Hubsignal2 is equal to CN HubTDMACS .

19. The non-transitory computer medium of claim 17 , further storing instructions for:

determining that the external condition is hub fade and there is no uplink power control at the hub when the hub determines that a downlink component plus a noise component of the first signal is function only of CN Hubsignal1 and CN HubSCPCCS .

20. The non-transitory computer medium of claim 19 , further storing instructions for:

maintaining the transmission power of the remote when the hub fade condition is determined.

21. The non-transitory computer medium of claim 17 , further storing instructions for:

determining that the external condition is hub fade and there is uplink power control (UPC) at the hub when the hub determines that a downlink component plus a noise component of the first signal is the difference between CN Hubsignal1 and CN HubSCPCCS .

22. The non-transitory computer medium of claim 21 , further storing instructions for:

maintaining the transmission power of the remote when the hub fade condition with UPC is determined.

23. The non-transitory computer medium of claim 17 , further storing instructions for:

determining that the external condition is remote fade when the hub determines that a target value is different from CN Hubsignal2 .

24. The non-transitory computer medium of claim 23 , further storing instructions for:

estimating the target value as the difference between CN HubTDMACS and a downlink component plus a noise component of the first signal.

25. The non-transitory computer medium of claim 17 , further storing instructions for:

determining the CN Hubsignal1 and CN Hubsignal2 periodically.

26. A method for adjusting a transmission power of a remote that exchanges data with a hub via a repeater, comprising:

operating the hub with uplink power control having a power control margin corresponding to a magnitude of a hub side uplink fade condition that can be overcome by the uplink power control;

measuring a carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to a repeater and back to the hub using a first signal;

measuring a carrier-to-noise ratio CN Hubsignal2 of data transmitted from a remote to the hub via the repeater using a second signal;

storing a predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using the first signal under a clear sky condition;

storing a predetermined carrier-to-noise ratio CN HubTDMACS of data transmitted from the hub to the repeater and back to the hub using the second signal under a clear sky condition;

evaluating a value of a first predetermined function at an arithmetic combination of (a) the power control margin of the hub, (b) the predetermined carrier-to-noise ratio CN HubSCPCCS of data transmitted from the hub to the repeater and back to the hub using the first signal under the clear sky condition, and (c) a measured carrier-to-noise ratio CN Hubsignal1 of data transmitted from the hub to the repeater and back to the hub using the first signal;

determining an external condition to be a deep fade condition when a magnitude of the external condition is greater than a difference between the clear sky condition and an evaluated value of a second predetermined function at the power control margin of the hub; and

adjusting a transmission power of the remote, depending on the external condition determined to be the deep fade condition, based on the CN Hubsignal1 , CN Hubsignal2 , CN HubSCPCCS , CN HubTDMACS , and the evaluated value of the first predetermined function based on the power control margin of the hub.