Method and apparatus for supervising transmit power in a high data rate system

• US 6,377,814 B1
• Filed: 02/07/2000
• Issued: 04/23/2002
• Est. Priority Date: 02/07/2000
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Bender, Paul E.
• Primary Examiner(s): Kincaid, Lester G.
• Application Number:
  US09/500,360
• Time in Patent Office: 806 Days
• Field of Search: 455/522, 455/63, 455/67.1, 455/67.3, 455/68, 455/69, 455/114, 455/115, 455/126, 455/127, 455/421, 455/572, 455/574, 455/561, 455/562, 370/206, 370/320, 370/335, 370/342, 370/311, 375/219, 375/220
• US Class Current: 455/522
• CPC Class Codes: H04W 52/20 using error rate
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 76/30 Connection release

Abstract

A method of supervising on the forward link in a high data rate system is disclosed, wherein a base station transmits to an access terminal on a forward traffic channel only when the base station has data to send to the access terminal. Each access terminal generates periodic data rate measurements based on the received forward link signal. Each access terminal then minimizes the period in which it transmits on the reverse link without being power-controlled by turning off its transmitter based on the data rate measurements.

Claims

1. In a wireless communication system, a method for controlling transmission power comprising the steps of:

measuring a set of characteristics of a received signal;

generating one or more data rate control (DRC) values based on the set of characteristics; and

turning off a transmitter based on the one or more DRC values.

2. The method of claim 1 wherein said step of measuring a set of characteristics further comprises the sub-step of:

measuring a carrier-to-interference ratio of the received signal.

3. The method of claim 1 wherein said step of turning off a transmitter further comprises the sub-steps of:

determining the length of time during which none of the generated DRC values exceeded a rate of zero; and

turning off the transmitter when the length of time is greater than or equal to a predetermined period.

4. The method of claim 3 wherein said predetermined period is approximately 240 milliseconds.

5. The method of claim 1 further comprising the steps of:

determining the length of time during which none of the generated DRC values indicated a rate of zero; and

turning on the transmitter when the length of time is greater than or equal to a predetermined period.

6. The method of claim 5 wherein said predetermined period is approximately 13 and one third milliseconds.

7. The method of claim 5 wherein said predetermined period is approximately 26 and two thirds milliseconds.

8. A wireless access terminal apparatus comprising:

a transmitter for amplifying and transmitting a transmit signal at a transmit power level;

a demodulator for demodulating a downconverted signal and generating a set of measurements of signal characteristics based on the downconverted signal; and

a control processor for evaluating the measurements, generating one or more data rate control (DRC) values based on the set of characteristics, and setting the transmit power level to approximately zero based on the one or more DRC values.

9. The apparatus of claim 8 wherein said control processor is further configured to evaluate a carrier-to-interference ratio from the set of measurements and to generate the DRC values based on the carrier-to-interference ratio.

10. The apparatus of claim 8 wherein said control processor is further configured to determine the length of time during which none of the generated DRC values exceeded a rate of zero, and to set the transmit power level to approximately zero based on when the length of time is greater than or equal to a predetermined transmitter-off period.

11. The apparatus of claim 10 wherein said control processor is configured to use a transmitter-off period of approximately 240 milliseconds.

12. The apparatus of claim 8 wherein said control processor is further configured to determine the length of time during which none of the generated DRC values indicated a rate of zero, and set the transmit power level to a value other than approximately zero when the length of time is greater than or equal to a predetermined transmitter-on period.

13. The apparatus of claim 12 wherein said control processor is further configured to use a transmitter-on period of approximately 13 and one third milliseconds.

14. The apparatus of claim 12 wherein said control processor is further configured to use a transmitter-on period of approximately 26 and two thirds milliseconds.

15. A wireless access terminal apparatus comprising:

means for measuring a set of characteristics of a received signal; and

means for generating one or more data rate control (DRC) values based on the set of characteristics and turning off a transmitter based on the one or more DRC values.

16. The apparatus of claim 15 further comprising means for measuring a carrier-to-interference ratio of the received signal.

17. The apparatus of claim 16 further comprising:

means for determining the length of time during which none of the generated DRC values exceeded a rate of zero; and

means for turning off the transmitter when the length of time is greater than or equal to a predetermined period.