Dynamic power control with adaptive reference level

• US 6,219,528 B1
• Filed: 06/29/1998
• Issued: 04/17/2001
• Est. Priority Date: 06/29/1998
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Original Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Inventors: Tsao, Jean, Wright, David A., Justiss, James E.
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): BEAMER, TEMICA M
• Application Number:
  US09/106,651
• Time in Patent Office: 1,023 Days
• Field of Search: 455/9, 455/12.1, 455/13.1, 455/13.4, 455/427, 455/428, 455/429, 455/522, 455/69, 455/115, 455/430, 370/316, 370/318, 370/321
• US Class Current: 455/13.4
• CPC Class Codes: H04B 7/18543 for adaptation of transmission parameters, e.g. power control for detecting or preventing errors in the information received H04L1/00
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/225 Calculation of statistics, e.g. average, variance

Abstract

The disclosure describes a method of adjusting a reference level for uplink signal power for use in a dynamic power control system with satellite-based measurements in a satellite communications system. The uplink signal power for a plurality of received uplink signals is measured and combined to determine whether a signal power reference level requires adjustment. The signal powers of a plurality of uplink signals are measured at the satellite and the received signals are validated to ensure the signals are acceptable for use in adjusting the reference level. The valid signals are used to calculate an average signal power of the measured uplink signal powers, with the calculated average being compared to the current value of the reference level. Based on the comparison, the reference level either retains the current value or is reset to an adjusted value.

Claims

1. A method of adjusting a reference level for use in a dynamic power control system with satellite-based measurements in a satellite communications system, the method comprising the steps of:

measuring an uplink signal power of a plurality of uplink signals received at a satellite, the uplink signals transmitted by a plurality of terminals;

determining whether each received uplink signal is a valid signal for use in adjusting the reference level, said reference level being a function of the uplink power received at the satellite;

comparing the measured uplink signal powers of the valid signals to a current value of the reference level; and

adjusting the reference level to an adjusted value based on result of the comparison step.

2. The method of claim 1, wherein the determination step further comprises the step of determining that a received uplink signal is an invalid signal where the received uplink signal arrives at the satellite in an unassigned time slot.

3. The method of claim 1, wherein the determination step further comprises the step of determining that a first received uplink signal is an invalid signal where the first received uplink signal arrives at the satellite concurrently with a second received uplink signal.

4. The method of claim 1, wherein the determination step further comprises the step of determining that a received uplink signal is an invalid signal where the received uplink signal is not authorized for receipt by the satellite.

5. The method of claim 1, wherein the comparison step further comprises the steps of:

calculating an average of the measured uplink signal powers of the valid signals; and

comparing the calculated average of the measured uplink signal powers to the current value of the reference level.

6. The method of claim 5, wherein the calculating step further comprises the step of calculating the average of the measured uplink signal powers of uplink signals received in a plurality of time slots.

7. The method of claim 5, wherein the calculating step further comprises the step of calculating the average of the measured uplink signal powers of uplink signals received in a plurality of carrier frequencies.

8. The method of claim 5, wherein the comparison step further comprises the step of comparing a difference between the calculated average and the current value of the reference level to a design goal.

9. The method of claim 1, wherein the reference level is stored at the satellite.

10. The method of claim 1, wherein the reference level is stored at a terminal and further comprising the step of transmitting information of the measured uplink signal powers to the terminal.

11. The met hod of claim 10, wherein the satellite calculates the adjusted value.

12. The method of claim 1, wherein the adjusting step further comprises the steps of:

transmitting information of the measured uplink signal powers to a remote location;

determining the adjusted value of the reference level at the remote location; and

transmitting the adjusted value to the satellite and the terminals.

13. The method of claim 12, wherein the remote location is one of a control station and a monitoring terminal.

14. A method of adjusting a reference level having a current value for use in a dynamic power control system with satellite-based measurements in a satellite communications system, the method comprising the steps of:

measuring an uplink signal power of a plurality of uplink signals received at a satellite, the uplink signals transmitted by a plurality of terminals;

determining whether a received uplink signal is a valid signal for use in adjusting the reference level, said reference level being a function of the uplink power received at the satellite, a received uplink signal being an invalid signal for one of arriving at the satellite in an unassigned time slot, arriving at the satellite concurrently with a second received uplink signal, and not being authorized for receipt by the satellite;

comparing the measured uplink signal powers of the valid signals to the current value of the reference level; and

adjusting the reference level to an adjusted value based on a result of the comparison step.

15. The method of claim 14, wherein the comparison step further comprises the steps of:

calculating an average of the measured uplink signal powers of the valid signals; and

comparing the calculated average of the measured uplink signal powers to the current value of the reference level.

16. The method of claim 15, wherein the calculating step further comprises the step of calculating the average of the measured uplink signal powers of uplink signals received in a plurality of time slots.

17. The method of claim 15, wherein the calculating step further comprises the step of calculating the average of the measured uplink signal powers of uplink signals received in a plurality of carrier frequencies.

18. The method of claim 15, wherein the comparison step further comprises comparing a difference between the calculated average and the current value of the reference level to a design goal.

19. The method of claim 14, wherein the reference level is stored at the satellite.

20. The method of claim 14, wherein the reference level is stored at a terminal and further comprising the step of transmitting information of the measured uplink signal powers to the terminal.

21. The method of claim 20, wherein the satellite calculates the adjusted value.

22. The method of claim 14, wherein the adjusting step further comprises the steps of:

transmitting information of the measured uplink signal powers to a remote location;

determining the adjusted value of the reference level at the remote location; and

transmitting the adjusted value to the satellite and the terminals.

23. The method of claim 22, wherein the remote location is one of a control station and a monitoring terminal.