Power control for wireless communication systems

• US 8,855,001 B2
• Filed: 05/16/2012
• Issued: 10/07/2014
• Est. Priority Date: 06/13/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Gorokhov, Alexei, Khandekar, Aamod, Kadous, Tamer, Borran, Mohammad J.
• Primary Examiner(s): MURPHY, RHONDA L
• Application Number:
  US13/473,229
• Publication Number:
  US 20120224502A1
• Time in Patent Office: 874 Days
• Field of Search: None
• US Class Current: 370/252
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff

Abstract

Techniques for controlling transmit power of a terminal are described. The terminal may send a first transmission (e.g., for pilot or signaling) on the reverse link, receive feedback (e.g., a power control command or an erasure indicator) for the first transmission, and adjust a reference power level based on the feedback. The terminal may also receive interference information and possibly other parameters such as a pilot quality indicator (PQI), an offset factor, and a boost factor from a sector. The terminal may determine transmit power for a second transmission to the sector based on the interference information, the reference power level, and/or the other parameters. The terminal may receive the feedback from one sector and may send the second transmission with CDMA or OFDMA to the same sector or a different sector.

Claims

1. An apparatus comprising:

at least one processor configured to send a pilot on a reverse link, to receive a pilot quality indicator (PQI) determined by a sector based on the pilot sent on the reverse link, to receive interference information from the sector, the interference information representative of interference for the entire sector, and to determine transmit power for a transmission on the reverse link based on the PQI, the received interference information, and transmit power for the pilot; and

a memory coupled to the at least one processor.

2. The apparatus of claim 1, wherein the PQI comprises a pilot carrier-over-thermal ratio PCoT) or a pilot carrier-to-interference ratio (C/I).

3. The apparatus of claim 1, wherein the at least one processor is configured to receive a power control (PC) command for the pilot and to adjust the transmit power for the pilot based on the PC command.

4. The apparatus of claim 1, wherein the interference information comprises a rise over thermal ratio (RoT), and

wherein the at least one processor is further configured to send the transmission at the determined transmit power with Code Division Multiple Access (CDMA).

5. The apparatus of claim 1, wherein the interference information comprises an interference over thermal ratio (IoT), and

wherein the at least one processor is further configured to send the transmission at the determined transmit power with Orthogonal Frequency Division Multiple Access (OFDMA).

6. The apparatus of claim 1, wherein the at least one processor is configured to, when sending the pilot, send the pilot with Code Division Multiple Access (CDMA), and to, when sending the transmission, send the transmission with Orthogonal Frequency Division Multiple Access (OFDMA).

7. A method comprising:

sending a pilot on a reverse link;

receiving a pilot quality indicator (PQI) determined by a sector based on the pilot sent on the reverse link;

receiving interference information from the sector, the interference information representative of interference for the entire sector; and

determining transmit power for a transmission on the reverse link based on the PQI, the received interference information, and transmit power for the pilot.

8. The method of claim 7,

wherein the interference information comprises a rise over thermal ratio (RoT), and

wherein the method further comprises sending the transmission at the determined transmit power with Code Division Multiple Access (CDMA).

9. The method of claim 7,

wherein the interference information comprises an interference over thermal ratio (IoT), and

wherein the method further comprises sending the transmission at the determined transmit power with Orthogonal Frequency Division Multiple Access (OFDMA).

10. An apparatus comprising:

means for sending pilot on a reverse link;

means for receiving a pilot quality indicator (PQI) determined by a sector based on the pilot sent on the reverse link;

receiving interference information from the sector, the interference information representative of interference for the entire sector; and

means for determining transmit power for a transmission on the reverse link based on the PQI, the received interference information, and transmit power for the pilot.

11. The apparatus of claim 10,

wherein the interference information comprises a rise over thermal ratio (RoT), and

wherein the apparatus further comprises means for sending the transmission at the determined transmit power with Code Division Multiple Access (CDMA).

12. The apparatus of claim 10,

wherein the interference information comprises an interference over thermal ratio (IoT), and

wherein the apparatus further comprises means for sending the transmission at the determined transmit power with Orthogonal Frequency Division Multiple Access (OFDMA).

13. An apparatus comprising:

at least one processor configured to receive a pilot from a terminal on a reverse link, to determine a pilot quality indicator (PQI) based on the received pilot, to send the PQI to the terminal, to send interference information representative of interference determined for the entire sector, and to receive a transmission sent by the terminal at a transmit power determined based on the PQI and the sent interference information; and

a memory coupled to the at least one processor.

14. The apparatus of claim 13, wherein the at least one processor is configured to determine a pilot carrier-over-thermal ratio (PCoT) based on the received pilot and to determine the PQI based on the pilot PCoT.

15. The apparatus of claim 13, wherein the at least one processor is configured to determine a pilot carrier-to-interference ratio (C/I) based on the received pilot and to determine the PQI based on the pilot C/I.