Modified power control for hybrid ARQ on the reverse link

• US 20040137931A1
• Filed: 01/10/2003
• Published: 07/15/2004
• Est. Priority Date: 01/10/2003
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Tiedemann, Edward G. Jr., Chen, Tao, Sarkar, Sandip
• Granted Patent: US 7,155,249 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 52/48 during retransmission after error or non-acknowledgment
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment

Abstract

A method for power control in a wireless communication system. An initial transmission of a data frame in the reverse link is received, and a first energy level of the data frame is measured. An energy deficit in the first energy level is then measured if the first energy level is insufficient to correctly decode the data frame, so that when the data frame is retransmitted with a second energy level equal to a difference between the first energy level and the energy deficit, the data frame can be correctly decoded with combined energy of the first energy level and the second energy level.

Claims

1. A method for power control in a wireless communication system, comprising:

receiving an initial transmission of a data frame in a reverse link of the communication system;

measuring a first energy level of the data frame; and

estimating an energy deficit in the first energy level if the first energy level is insufficient to correctly decode the data frame, so that when the data frame is retransmitted with a second energy level equal to a difference between the first energy level and the energy deficit, the data frame can be correctly decoded with combined energy of the first energy level and the second energy level.

2. The method of claim 1, wherein measuring a first energy level of the data frame includes measuring an energy level of a traffic channel in the reverse link.

3. The method of claim 2, wherein the traffic channel is a reverse supplemental channel (R-SCH) of the communication system.

4. The method of claim 2, wherein measuring a first energy level of the data frame also includes measuring an energy level of a pilot channel in the reverse link.

5. The method of claim 4, wherein measuring a first energy level of the data frame further includes computing a ratio between the energy level of the traffic channel and the energy level of the pilot channel.

6. The method of claim 1, further comprising:

estimating a total energy level sufficient to correctly decode the data frame.

7. The method of claim 1, further comprising:

transmitting the energy deficit on a forward acknowledgement channel, along with an appropriate negative acknowledgement for the receipt of the data frame.

8. A method for controlling power on a reverse link of a wireless communication system, comprising:

computing a ratio between an energy level of a data frame and a pilot channel energy transmitted on the reverse link;

estimating an energy deficit ratio if the data frame has been received with an error, such that the energy deficit ratio enables a remote terminal to adjust the energy level of the data frame so the data frame can be correctly decoded in a retransmission when the energy level of the data frame is combined with an energy level of the retransmission.

9. A reverse link power controller in a wireless communication system, comprising:

means for receiving an initial transmission of a data frame in the reverse link;

measuring means for measuring a first energy level of the data frame; and

estimating means for estimating an energy deficit in the first energy level if the first energy level is insufficient to correctly decode the data frame, so that when the data frame is retransmitted with a second energy level equal to a difference between the first energy level and the energy deficit, the data frame can be correctly decoded with combined energy of the first energy level and the second energy level.

10. The power controller of claim 9, wherein the measuring means includes means for measuring an energy level of a traffic channel in the reverse link.

11. The power controller of claim 10, wherein the traffic channel is a reverse supplemental channel (R-SCH) of the communication system.

12. The power controller of claim 10, wherein the measuring means includes means for measuring an energy level of a pilot channel in the reverse link.

13. The power controller of claim 12, wherein the measuring means includes means for computing a ratio between the energy level of the traffic channel and the energy level of the pilot channel.

14. The power controller of claim 9, further comprising:

means for estimating a total energy level sufficient to correctly decode the data frame.

15. The power controller of claim 9, further comprising:

means for transmitting the energy deficit on a forward acknowledgement channel of the communication system, along with an appropriate negative acknowledgement for the receipt of the data frame.

16. A reverse link power controller in a wireless communication system, comprising:

a receiver configured to receive an initial transmission of a data frame in a reverse link of the communication system;

a measurement apparatus configured to measure a first energy level of the data frame; and

an estimating apparatus configured to estimate an energy deficit in the first energy level if the first energy level is insufficient to correctly decode the data frame, so that when the data frame is retransmitted with a second energy level equal to a difference between the first energy level and the energy deficit, the data frame can be correctly decoded with combined energy of the first energy level and the second energy level.

17. The power controller of claim 16, wherein the measurement apparatus includes a first measuring device configured to measure an energy level of a traffic channel in the reverse link.

18. The power controller of claim 17, wherein the traffic channel is a reverse supplemental channel (R-SCH) of the communication system.

19. The power controller of claim 17, wherein the measurement apparatus also includes a second measuring device configured to measure an energy level of a pilot channel in the reverse link.

20. The power controller of claim 19, wherein the measurement apparatus further includes a computing device configured to compute a ratio between the energy level of the traffic channel and the energy level of the pilot channel.

21. The power controller of claim 16, further comprising:

an estimator configured to estimate a total energy level sufficient to correctly decode the data frame.

22. The power controller of claim 16, further comprising:

a transmitter configured to transmit the energy deficit on a forward acknowledgement channel, along with an appropriate negative acknowledgement for the receipt of the data frame.

23. A base station for a wireless communication system, the base station comprising:

an RF front end configured to receive and appropriately amplify, filter, and process a reverse link traffic channel data frame from a remote terminal;

a digital signal processor (DSP) adapted to demodulate and further process the received data frame; and

a power controller including;

a measurement apparatus configured to measure a first energy level of the data frame; and

an estimating apparatus configured to estimate an energy deficit in the first energy level if the first energy level is insufficient to correctly decode the data frame, so that when the data frame is retransmitted with a second energy level equal to a difference between the first energy level and the energy deficit, the data frame can be correctly decoded with combined energy of the first energy level and the second energy level.

24. The base station of claim 23, wherein the measurement apparatus includes a first measuring device configured to measure an energy level of a traffic channel in the reverse link.

25. The base station of claim 24, wherein the traffic channel is a reverse supplemental channel (R-SCH) of the communication system.

26. The base station of claim 24, wherein the measurement apparatus also includes a second measuring device configured to measure an energy level of a pilot channel in the reverse link.

27. The base station of claim 26, wherein the measurement apparatus further includes a computing device configured to compute a ratio between the energy level of the traffic channel and the energy level of the pilot channel.

28. The base station of claim 23, further comprising:

an estimator configured to estimate a total energy level sufficient to correctly decode the data frame.

29. The base station of claim 23, further comprising:

a transmitter configured to transmit the energy deficit on a forward acknowledgement channel, along with an appropriate negative acknowledgement for the receipt of the data frame.