Method and apparatus for performing fast power control in a mobile communication system

• US 6,137,840 A
• Filed: 11/15/1995
• Issued: 10/24/2000
• Est. Priority Date: 03/31/1995
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Tiedemann, Edward G. Jr., Chen, Tao
• Primary Examiner(s): Pham, Chi H.
• Assistant Examiner(s): Corrielus, Jean B.
• Application Number:
  US08/559,386
• Time in Patent Office: 1,805 Days
• Field of Search: 375/297, 375/296, 375/254, 375/284, 375/278, 375/285, 375/395, 375/299, 375/222, 375/225, 375/345, 370/352, 370/318, 370/317, 371/505, 455/116, 455/126, 455/127, 455/68, 455/69, 455/522, 714/708
• US Class Current: 375/297
• CPC Class Codes: H04W 52/08 Closed loop power control
• CPC Class Codes: H04W 52/228 using past power values or information
• CPC Class Codes: H04W 52/245 taking into account received signal strength
• CPC Class Codes: H04W 52/265 taking into account the quality of service QoS
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 52/28 using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non transmission
• CPC Class Codes: H04W 52/282 taking into account the speed of the mobile
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/362 Aspects of the step size

Abstract

A method and apparatus for controlling transmission power in a mobile communication system is disclosed. The method disclosed provides for a closed-loop power control method for variable rate transmissions. The power of transmissions is varied in accordance with the rate of the frames of data being transmitted. The transmission power between the rates can be a fixed or variable difference.

Claims

1. An apparatus for controlling transmission power of variable rate frames of data, comprising:

control processor means for providing a transmit power signal, wherein said control processor means is for determining a reference rate transmit power level and for determining at least one additional transmit power level in accordance with said reference rate transmit power;

variable gain transmitter means for receiving said transmit power signal and for amplifying said variable rate frames in accordance with said transmit power signal and a rate of said variable rate frames of data;

receiver means for receiving frame quality message from a remote communication station and wherein said control processor means is responsive to said frame quality message; and

summing means for receiving a gain adjustment value and a previous reference rate transmit value, and for summing said gain adjustment value and said previous reference rate transmit value to provide said reference rate transmit power signal.

2. The apparatus of claim 1 further comprising second summing means for receiving said reference rate transmit power level and for receiving a fixed difference value and for summing said reference rate transmit power level and said fixed difference value to determine said at least one additional transmit power level.

3. The apparatus of claim 1 further comprising a variable difference calculator means for providing a variable difference value, wherein said summing means receives said reference rate transmit power level and said variable difference value, and sums said reference rate transmit power level and said variable difference value to determine said at least one additional transmit power level.

4. The apparatus of claim 3 further comprising frame error rate monitor means for determining at least one frame error rate value and wherein said variable difference calculator means is responsive to said at least one frame error rate value.

5. The apparatus of claim 4 wherein said frame error rate monitor means comprises:

demultiplexer means for receiving said frame quality message and for outputting said frame quality message upon a selected output in accordance with a frame quality message rate; and

plurality of frame error rate counter means each of said plurality of frame error rate counter means coupled to a corresponding output of said demultiplexer means.

6. An apparatus for controlling transmission power of variable rate frames of data, comprising:

control processor means for providing a transmit power signal;

variable gain transmitter means for receiving said transmit power signal and for amplifying said variable rate frames in accordance with said transmit power signal and a rate of said variable rate frames of data;

receiver means for receiving a frame quality message from a remote communication station;

demtltiplexer means for receiving said frame quality message and for outputting said frame quality message upon a selected output in accordance with a frame quality message rate; and

plurality of transmit power calculators, each of said transmit power calculators coupled to a corresponding output of said demultiplexer and for providing said transmit power signal, wherein each of said plurality of transmit power calculators comprises;

gain adjustment selector means for receiving said frame quality message and for selecting a gain adjustment value in accordance with said frame quality and

summing means for receiving a previous transmit power value and for receiving said gain adjustment value and for summing said previous transmit power value and said gain adjustment value to provide said transmit power signal.

7. The apparatus of claim 6 wherein said control processor means comprises:

first transmit power calculator means for receiving said frame quality message and for determining a plurality of first transmit power level values; and

second transmit power level calculator means for receiving at least one of said plurality of first transmit power level values and for determining at least one remaining second transmit power level value in accordance with said at least one of said plurality of first transmit power level values, wherein said first and second transmit power level values are used to provide said transmit power signal.

8. The apparatus of claim 7 wherein said frequent rate transmit power calculator means comprises:

reference rate calculator means for receiving a first set of selected frame quality messages and for determining a reference rate transmit power level value in accordance with said first set of selected frame quality messages; and

at least one additional frequent rate transmit power calculator means for receiving a second set of selected frame quality messages and for determining at least one additional reference rate transmit power level value in accordance with said second set of selected frame quality messages.

9. The apparatus of claim 8 wherein said at least one additional frequent rate transmit power calculator means is responsive to said reference rate transmit power level value.

10. The apparatus of claim 8 wherein said reference rate calculator means is responsive to said at least one additional reference rate transmit power level value.

11. The apparatus of claim 8 wherein said reference rate calculator means comprises:

gain adjust selector means for receiving said first set of selected frame quality messages and for providing a reference rate gain adjustment value in accordance with said first set of selected frame quality messages; and

reference rate transmit power adjustment means for modifying said reference rate transmit power level value in accordance with said reference rate gain adjustment value.

12. The apparatus of claim 11 wherein said reference rate power adjustment means comprises:

summing means for summing said reference rate gain adjustment value and a previous reference rate transmit power level value to provide said reference rate transit power value; and

delay means for providing said previous reference rate transmit power level value.

13. The apparatus of claim 12 wherein said reference rate transmit power adjustment means further comprise second summing means for receiving said at least one additional reference rate transmit power level value and for adjusting said at least one additional reference rate transmit power level value by a predetermined value to provide said reference rate transmit power value.

14. An apparatus for controlling transmission power of variable rate frames of data, comprising:

control processor means for providing a transmit power signal, wherein said control processor means is for determining a reference rate transmit power level and for determining at least one additional reference rate transmit power level in accordance with said reference rate transmit power, wherein said control processor means comprises;

first calculator means for receiving a first set of selected frame quality messages and for determining a first transmit power level value in accordance with said first set of selected frame quality messages;

at least one additional calculator means for receiving a second set of selected frame quality messages and for determining at least one additional transmit power level value in accordance with said second set of selected frame quality messages; and

composite reference calculator means for receiving said first transmit power level value and said at least one additional transmit power level value and for determining a reference rate transmit power value in accordance with said first transmit power level value and said at least one additional transmit power level value;

variable gain transmitter means for receiving said transmit power signal and for amplifying said variable rate frames in accordance with said transmit power signal and a rate of said variable rate frames of data; and

receiver means for receiving frame quality message from a remote communication station and wherein said control processor means is responsive to said frame quality message.

15. The apparatus of claim 14 further comprising weighting means interposed between said at least one additional calculator means and said composite reference calculator means for weighting said at least one additional transmit power level value in accordance with a predetermined weighting format.

16. The apparatus of claim 15 wherein said weighting means comprises multiplier means for receiving said at least one additional transmit power level value and multiplying said at least one additional transmit power level value by a weighting factor.

17. The apparatus of claim 16 wherein said weighting factor is a predetermined fixed value.

18. The apparatus of claim 14 further comprising remaining rate transmit calculator means for receiving said reference rate transmit power value and for determining said at least one additional transmit power level value in accordance with said reference rate transmit power value.

19. An apparatus for controlling transmission power of variable rate frames of data, comprising:

control processor means for providing a transmit power signal, wherein said control processor means comprises;

first calculator means for receiving a first set of selected frame quality messages and for determining a first transmit power level value in accordance with said first set of selected frame quality messages;

at least one additional calculator means for receiving a second set of selected frame quality messages and for determining at least one additional transmit power level value in accordance with said second set of selected frame quality messages;

composite reference calculator means for receiving said first transmit power level value and said at least one additional transmit power level value and for determining a reference rate transmit power value in accordance with said first transmit power level value and said at least one additional transmit power level value; and

wherein said control processor means is for determining a reference rate transmit power level and for determining at least one additional transmit power level in accordance with said reference rate transmit power value;

variable gain transmitter means for receiving said transmit power signal and for amplifying said variable rate frames in accordance with said transmit power signal and a rate of said variable rate frames of data;

receiver means for receiving frame quality message from a remote communication station and wherein said control processor means is responsive to said frame quality message;

weighting means interposed between said at least one additional calculator means and said composite reference calculator means for weighting said at least one additional transmit power level value in accordance with a predetermined weighting format, wherein said weighting means comprises multiplier means for receiving said at least one additional transmit power level value and multiplying said at least one additional transmit power level value by a weighting factor, wherein said weighting factor is a predetermined fixed value; and

weighting factor calculator means for calculating said fixed value.

20. The apparatus of claim 19 wherein said weighting factor calculator means is responsive to a frame error rate statistic.

21. The apparatus of claim 19 wherein said weighting factor calculator means is responsive to a rate frequency value.

22. An apparatus for controlling transmission power of variable rate frames of data, comprising:

receiver means for receiving frame quality message from a remote communication station;

control processor means for determining a reference rate transmit power level and at least one additional reference rate transmit power level in accordance with said reference rate transmit power level, wherein said control processor means is responsive to said frame quality message, and wherein said control processor means comprises gain adjust selector means for selecting a gain adjustment value responsive to said frame quality message;

summing means for receiving said gain adjustment value and a previous reference rate transmit value, and for summing said gain adjustment value and said previous reference rate transmit value to provide said reference rate transmit power level; and

variable gain transmitter means for receiving said reference rate transmit power level and for amplifying said variable rate frames in accordance with said reference rate transmit power level and a rate of said variable rate frames of data.

23. An apparatus for controlling transmission power of variable rate frames of data, comprising:

receiver means for receiving frame quality message from a remote communication station;

control processing means for providing a transmit power signal, and determining a reference rate transmit power level and at least one additional transmit power level in accordance with said reference rate transmit power level, wherein said control processor means is responsive to said frame quality message, and wherein said control processor comprises;

first rate transmit power level calculator means for receiving said frame quality message and for determining a plurality of first rate transmit power level values;

second rate transmit power level calculator means for receiving at least one of said plurality of first transmit power level values and for determining at least one remaining transmit power level value in accordance with said at least one of said plurality of first transmit power level values, wherein said first and second transmit power level values are used to provide said transmit power signal; and

variable gain transmitter means for receiving said transmit power signal as provided by said control processing means, and for amplifying said variable rate frame in accordance with said transmit power signal and a rate of said variable rate frames of data.

24. An apparatus for controlling transmission power of variable rate frames of data, comprising:

receiver means for receiving frame quality message from a remote communication station;

control processor means for providing a transmit power signal, and determining a reference rate transmit power level and at least one additional transmit power level in accordance with said reference rate transmit power level, wherein said control processor means is responsive to said frame quality message, and wherein said control processor comprises;

first calculator means for receiving a first set of selected frame quality messages and for determining a first transmit power level value in accordance with said first set of selected frame quality messages;

at least one additional calculator means for receiving a second set of selected frame quality messages and for determining at least one additional transmit power level value in accordance with said second set of selected frame quality messages;

composite calculator means for receiving said first transmit power level value and said at least one additional transmit power level value, and for determining a transmit power value in accordance with said first transmit power level value and said at least one additional transmit power level wherein said composite calculator means is coupled to said first calculator means and said control processor means; and

variable gain transmitter means for receiving said transmit power value and for amplifying said variable rate frames of data in accordance with said transmit power value and a rate of said variable rate frames of data.

25. An apparatus for controlling transmission power of variable rate frames of data, comprising:

a control processor configured to receive a frame quality indicator (FQI) message indicating a quality value, and to determine a reference rate transmit power level by selecting a gain adjustment value, the gain adjustment value being determined based upon the quality value of the FQI message; and

at least one sumning element associated with a particular transmit data rate and configured to receive both the reference rate transmit power level and a predetermined value having a fixed value, each summing element outputting a signal indicative of a transmit power level that is appropriate for the associated transmit data rate.

26. The apparatus of claim 25 wherein the predetermined value is calculated from an error value provided by at least one frame error rate (FER) counter, said at least one FER counter conveying the error value that is determined based upon the associated transmit data rate.

27. An apparatus for controlling transmission power of variable rate frames of data, comprising:

a control processor configured to receive a frame quality indicator (FQI) message indicating a quality value, to determine a first reference rate transmit power by selecting a first gain adjustment level value, and to determine a second reference rate transmit power level by selecting a second gain adjustment level vaule, each gain adjustment value being determined based upon the quality value of the FQI message; and

at least one summing element, said at least one summing element associated with a particular transmit data rate and configured to receive either the first reference rate transmit power level or the second reference rate transmit power level and a predetermined value, said at least one summing element outputting a signal indicative of a transmit power level that is appropriate for the associated transmit data rate, each predetermined value being calculated from an error value provided by at least one frame error rate (FER) counter, said at least one FER counter conveying the error value that is determined based upon the associated transmit data rate.

28. An apparatus for controlling transmission power of variable rate frames of data, comprising:

a control processor configured to receive a frame quality indicator (FQI) message indicating a quality value, and to determine a reference rate transmit power level by using at least one transmit power level which is determined by using a particular transmit data rate, a particular gain adjustment value and a particular weighting value, said particular gain adjustment value being determined based upon the quality value of the FQI message; and

at least one summing element, said at least one summing element associated with said particular transmit data rate and configured to receive said reference rate transmit power level and a predetermined value, said at least one summing element outputting a signal indicative of said transmit power level that is appropriate for said associated transmit data rate, said predetermined value being determined from an error value provided by at least one frame error rate (FER) counter, said at least one FER counter conveying the error value that is determined based upon the associated transmit data rate.

29. The apparatus of claim 28 wherein the weighting value is a fixed value.

30. The apparatus of claim 28 wherein the weighting value is calculated from a set of parameters based upon a statistical analysis of the error values associated with each transmit data rate.

31. The apparatus of claim 28 wherein the weighting value is not assigned a numerical quantity.