Reduction of power consumption in a portable communication unit

• US 5,293,639 A
• Filed: 03/09/1993
• Issued: 03/08/1994
• Est. Priority Date: 08/09/1991
• Status: Expired due to Term

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Branch, Tony R., Wilson, Alan L., Muri, David L.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): FAILE, ANDREW I
• Application Number:
  US08/028,530
• Time in Patent Office: 364 Days
• Field of Search: 455/13.4, 455/20, 455/34.1, 455/34.2, 455/54.1, 455/54.2, 455/67.3, 455/67.4, 455/69, 455/77, 455/88, 455/89, 455/127, 455/343, 455/17, 375/58
• US Class Current: 455/17
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04W 52/20 using error rate

Abstract

Power consumption in a portable communication unit (101) is reduced by first transmitting at a first time, a message (701) at a first transmit power level to a repeater (103) on a first communication channel. At a second time the message (701) is repeated (903) by the repeater on a second communication channel, thereby transmitting a delayed message (703). The portable communication unit (101) tunes (807) to the second communication channel after transmitting all of the message (701), so as to receive at least part of the delayed message (703). The repeater (103) establishes a receive quality metric (705) for the message (701) and transmits (909) the receive quality metric after all of the delayed message (703) is transmitted. The portable communication unit receives and stores (809) the receive quality metric (705), and determines a second transmit power level for transmitting another message using the receive quality metric.

Claims

1. A method of reducing power consumption in a portable communication unit, comprising the steps of:

transmitting at a first time, by the portable communication unit, a first message at a first transmit power level to a repeater on a first communication channel;

repeating at a second time, which second time is later than said first time, by said repeater, said first message, thereby transmitting a delayed message on a second communication channel;

tuning the portable communication unit to said second communication channel after transmitting all of said first message, so as to receive at least part of said delayed message;

establishing a receive quality metric for said first message at said repeater;

transmitting said receive quality metric appended to the end of said delayed message after all of said delayed message has been repeated;

receiving and storing in the portable communication unit said receive quality metric; and

determining, by the portable communication unit, a second transmit power level for transmitting a second message, said determining step using said stored receive quality metric.

2. The method of claim 1, wherein said determining step further comprises the steps of:

computing a time value from transmission of said first message to transmission of said second message; and

setting said second transmit power level to an initial power level when said time value has a first relationship with respect to a predetermined value.

3. The method of claim 1, wherein said receive quality metric represents a bit error rate measurement and wherein said determining step further comprises the step of decreasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a first relationship with respect to a predetermined value.

4. The method of claim 1, wherein said receive quality metric represents a bit error rate measurement and wherein said determining step further comprises the step of increasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a second relationship with respect to a predetermined value.

5. The method of claim 1, wherein said receive quality metric represents a received signal strength measurement and wherein said determining step further comprises the step of decreasing said first transmit power level to produce said second transmit power level when said received signal strength measurement has a first relationship with respect to a predetermined value.

6. The method of claim 1, wherein said receive quality metric represents a received signal strength measurement and wherein said determining step further comprises the step of increasing said first transmit power level to produce said second transmit power level when said received signal strength measurement has a second relationship with respect to a predetermined value.

7. The method of claim 1, further comprising the steps of:

computing a signal quality metric for said receive quality metric; and

decreasing said second transmit power level when said receive quality metric has a first relationship with respect to a predetermined value.

8. The method of claim 1, further comprising the steps of:

computing a signal quality metric for said receive quality metric; and

increasing said second transmit power level when said receive quality metric has a second relationship with respect to a predetermined value.

9. The method of claim 1, wherein said receive quality metric represents a bit error rate measurement and a received signal strength measurement and wherein said determining step further comprises the step of decreasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a first relationship with respect to a first predetermined value and said received signal strength measurement has said first relationship with respect to a second predetermined value.

10. The method of claim 1, wherein said receive quality metric represents a bit error rate measurement and a received signal strength measurement and wherein said determining step further comprises the step of increasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a second relationship with respect to a first predetermined value and said received signal strength measurement has said second relationship with respect to a second predetermined value.

11. A portable communication unit, comprising:

means for transmitting at a first time a first message at a first transmit power level to a repeater on a first communication channel;

means for tuning to a second communication channel after transmitting all of said first message, so as to receive at least part of a delayed message, which is comprised of said first message transmitted at a second time on said second communication channel;

means for receiving a receive quality metric from said repeater, wherein said receive quality metric, appended to the end of said delayed message, is transmitted after all of said first message is transmitted;

means for storing said receive quality metric; and

means, coupled to said means for storing, for determining a second transmit power level for transmitting a second message, said determining means using said receive quality metric.

12. The portable communication unit of claim 11, wherein said means for determining comprises:

means for computing a time value from transmission of said first message to transmission of said second message; and

means for setting said second transmit power level to an initial power level when said time value has a first relationship with respect to a predetermined value.

13. The portable communication unit of claim 11, wherein said receive quality metric represents a bit error rate measurement and wherein said determining means further comprises means for decreasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a first relationship with respect to a predetermined value.

14. The portable communication unit of claim 11, wherein said receive quality metric represents a bit error rate measurement and wherein said determining means further comprises means for increasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a second relationship with respect to a predetermined value.

15. The portable communication unit of claim 11, wherein said receive quality metric represents a received signal strength measurement and wherein said determining means further comprises means for decreasing said first transmit power level to produce said second transmit power level when said received signal strength measurement has a first relationship with respect to a predetermined value.

16. The portable communication unit of claim 11, wherein said receive quality metric represents a received signal strength measurement and wherein said determining means further comprises means for increasing said first transmit power level to produce said second transmit power level when said received signal strength measurement has a second relationship with respect to a predetermined value.

17. The portable communication unit of claim 11, further comprising:

means for computing a signal quality metric for said received receive quality metric; and

means for decreasing said second transmit power level when said receive quality metric has a first relationship with respect to a predetermined value.

18. The portable communication unit of claim 11, further comprising:

means for computing a signal quality metric for said received receive quality metric; and

means for increasing said second transmit power level when said receive quality metric has a second relationship with respect to a predetermined value.

19. The portable communication unit of claim 11, wherein said receive quality metric represents a bit error rate measurement and a received signal strength measurement and wherein said determining means further comprises means for decreasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a first relationship with respect to a first predetermined value and said received signal strength measurement has said first relationship with respect to a second predetermined value.

20. The portable communication unit of claim 11, wherein said receive quality metric represents a bit error rate measurement and a received signal strength measurement and wherein said determining means further comprises means for increasing said first transmit power level to produce said second transmit power level when said bit error rate measurement has a second relationship with respect to a first predetermined value and said received signal strength measurement has said second relationship with respect to a second predetermined value.