Method and apparatus for transmitting acknowledgement signals

• US 20030131299A1
• Filed: 01/02/2003
• Published: 07/10/2003
• Est. Priority Date: 01/05/2002
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Ahn, Joon Kui, Kwon, Hyuck Chan
• Granted Patent: US 7,143,330 B2
• Time in Patent Office: Days
• US Class Current: 714/748
• CPC Class Codes: H04L 1/1692 Physical properties of the supervisory signal, e.g. acknowledgement by energy bursts
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end
• CPC Class Codes: H04L 2001/125 Arrangements for preventing errors in the return channel
• CPC Class Codes: H04W 52/286 during data packet transmission, e.g. high speed packet access [HSPA]

Abstract

The present invention relates to a power controlling method in a mobile radio communication system using Automatic Repeat reQuest (ARQ) scheme, and more particularly to a power controlling method of response (ACK/NACK) signals for transmitting the ACK/NACK signals in different power based on the permissible probabilities of reception error that the system requires. When the ACK/NACK signals are transmitted and received in the automatic repeat request (ARQ) system, since the ACK/NACK signals can be transmitted in accordance with the transmission power satisfying an error rate required in each signal by differentiating the transmission power of the signal according to each ACK/NACK, the power consumption required in the transmission of the NACK signal can be reduced.

Claims

1. A method of transmitting two acknowledgement signals for received data packets comprising:

transmitting a first acknowledgement signal with a first prescribed power level difference from a reference power level; and

transmitting a second acknowledgement signal with a second prescribed power level difference from the reference power level, wherein the first prescribed power level difference and the second prescribed power level difference are different from each other.

2. The method of claim 1, wherein the transmission power levels of the two acknowledgement signals are determined based on a threshold value which is shifted from said reference power level to a direction of the power level of one of the two acknowledgement signals.

3. The method of claim 2, wherein the first acknowledgement signal is an ACK signal indicative of non-erroneous reception of a packet data and the second acknowledgement signal is a NACK signal indicative of erroneous reception of the packet data and said one of the two acknowledgement signals is ACK signal.

4. The method of claim 3, wherein the difference of the power level of an ACK signal and the threshold value is based on a probability of occurring an erroneous determination of the ACK signal as the other signal.

5. The method of claim 3, the difference of the power level of a NACK signal and the threshold value is based on a probability of occurring an erroneous determination of the NACK signal as the other signal.

6. The method of claim 3, wherein the difference of the power level of an ACK signal and the threshold value is less than the difference of the power level of a NACK signal and a threshold.

7. The method of claim 6, wherein the power level of a NACK signal is less than one half of the power level of an ACK signal.

8. The method of claim 2, wherein the threshold value is based on a probability of occurring an erroneous determination of no acknowledgement to one of the two acknowledgement signals.

9. The method of claim 1, wherein the reference power level is indicative of discontinuous transmission (DTX).

10. The method of claim 9, wherein the second prescribed power level difference is less than one half of the first prescribed power level difference.

11. An apparatus comprising:

a receiver for receiving data packets;

a transmitter for transmitting an ACK signal having a first power level and for transmitting a NACK signal having a second power level, wherein the second level is different from the first level.

12. The apparatus of claim 11, wherein the first power level is substantially equal to the required power level for avoiding a probability of an erroneous determination of the ACK signal as the NACK signal.

13. The apparatus of claim 11, wherein the second power level is substantially equal to a required power level for avoiding a probability of an erroneous determination of the NACK signal as the ACK signal.

14. A method of transmitting at least one acknowledgement signal using automatic repeat request (ARQ), comprising:

transmitting a first acknowledgement signal with a first prescribe power level difference from a reference power level; and

transmitting a second acknowledgement signal with a second prescribed power level difference from the reference power level, wherein the first prescribed power level difference and the second prescribed power level difference are different from each other.

15. The method of claim 14, wherein the first acknowledgement signal is determined based on a threshold value.

16. The method of claim 15, wherein the threshold value is relatively greater than the reference power level.

17. The method of claim 15, wherein the threshold value is based on a probability of avoiding an erroneous determination of discontinuous transmission (DTX) to one of the first and second acknowledgement signals.

18. The method of claim 14, wherein the first acknowledgement signal is an ACK signal indicative of non-erroneous reception of a packet data and the second acknowledgement signal is a NACK signal indicative of erroneous reception of the packet data.

19. The method of claim 14, wherein the second prescribed power level difference is at least one half of the first prescribed power level difference.

20. The method of claim 19, wherein the second prescribed power level is difference is less than one half of the first prescribed power level difference.

21. The method of claim 14, wherein the reference power level is indicative of discontinuous transmission (DTX).

22. The method of claim 18, wherein the first prescribed power level difference is based on a probability of avoiding an erroneous determination of the ACK signal as the NACK signal.

23. The method of claim 18, wherein the second prescribed power level difference is based on a probability of avoiding an erroneous determination of the NACK signal as the ACK signal.

24. An apparatus comprising:

means for receiving data;

means for transmitting an ACK signal having a first power level; and

means for transmitting a NACK signal having a second power level, wherein the second level is not based on the first level.

25. The apparatus of claim 24, wherein the first power level is substantially equal to the required power level for avoiding a probability of an erroneous determination of the ACK signal as the NACK signal.

26. The apparatus of claim 24, wherein the second power level is substantially equal to a required power level for avoiding a probability of an erroneous determination of the NACK signal as the ACK signal.

27. A method of avoiding error in a device using an ACK signal and a NACK signal based on automatic repeat request, comprising:

determining a required ACK signal power level to avoid a probability of erroneous determination of the ACK signal as the NACK signal;

determining an actual ACK transmission power of the device based on the required ACK power level;

determining a required NACK signal power level to avoid a probability of erroneous determination of the NACK signal as the ACK signal; and

determining an actual NACK transmission power of the device, wherein the actual NACK transmission power is independent of the actual ACK transmission power.

28. A method of transmitting ACK/NACK radio signal in a radio communication system comprising:

transmitting ACK signal with a first prescribed power level difference from a reference power level; and

transmitting NACK signal with a second prescribed power level difference from the reference power level, wherein the first prescribed power level difference and the second prescribed power level difference are different from each other.

29. The method of claim 28, wherein the transmission power levels of the ACK and NACK signals are determined based on a threshold power level which is shifted from said reference power level to a direction of the power level of the ACK signal.

30. The method of claim 29, wherein the difference of the power level of an ACK signal and the threshold power level is based on a probability of occurring an erroneous determination of the ACK signal.

31. The method of claim 29, wherein the difference of the power level of a NACK signal and the threshold power level is based on a probability of occurring an erroneous determination of the NACK signal.

32. The method of claim 28, wherein the absolute power level of a NACK signal is less than one half of the absolute power level of an ACK signal.