Controlling inter-cell interference in forward access channel (Cell—FACH) state

Patent metadata

Field	Value
Publication number	US-9516657-B2
Application number	US-201213436830-A
Country	US
Kind code	B2
Filing date	Mar 30, 2012
Priority date	Apr 1, 2011
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

Since common E-DCH resources may be assigned from a single Node B, uplink macro-diversity may not be possible between neighboring Node B's. In addition, a user equipment (UE) assigned a common E-DCH resource may not be allowed to perform cell reselection. Thus, maintaining the assignment of a common E-DCH resource to a given UE for more than a few hundred milliseconds may result in unacceptable inter-cell interference, for example, when the UE moves closer to a neighboring cell controlled by a non-serving Node B. To overcome inter-cell interference and allow a more extensive utilization of the Cell_FACH state, a method may be used to detect and/or control inter-cell interference.

First claim

What is claimed:

1. A method for adjusting a transmission power of a wireless transmit/receive unit (WTRU) on an enhanced relative grant channel (E-RGCH) for inter-cell interference, the method comprising:
measuring a serving cell channel quality for the WTRU and at least one neighbor cell channel quality for the WTRU;
comparing, in the WTRU, the at least one neighbor cell channel quality with the serving cell channel quality;
adding, in the WTRU, the at least one neighbor cell to a list of monitored cells, if for a time to trigger, the difference between the at least one neighbor cell channel quality and the serving cell channel quality exceeds a hysteresis threshold;
monitoring, at the WTRU, the E-RGCH for each cell in the list of monitored cells; and
adjusting the WTRU transmission power for commands on the E-RGCH for the monitored cells.

2. The method of claim 1 , further comprising determining a cell offset for each cell in the list of monitored cells.

3. The method of claim 2 , wherein adjusting the WTRU transmission power for commands on the E-RGCH for the monitored cells comprises using the cell offset for each cell.

4. The method of claim 1 , wherein the hysteresis threshold comprises a signal quality of the serving cell added to an offset.

5. A wireless/transmit receive unit (WTRU) that adjusts a transmission power of the wireless transmit/receive unit (WTRU) on an enhanced relative grant channel (E-RGCH) for inter-cell interference, the WTRU comprising:
a processor configured to:
measure a serving cell channel quality for the WTRU and at least one neighbor cell channel quality for the WTRU;
compare, in the WTRU, the at least one neighbor cell channel quality with the serving cell channel quality;
add, in the WTRU, the at least one neighbor cell to a list of monitored cells, if for a time to trigger, the difference between the at least one neighbor cell channel quality and the serving cell channel quality exceeds a hysteresis threshold;
monitor, at the WTRU, the E-RGCH for each cell in the list of monitored cells; and
adjust the WTRU transmission power for commands on the E-RGCH for the monitored cells.

6. The WTRU of claim 5 , wherein the processor is further configured to determine a cell offset for each cell in the list of monitored cells.

7. The WTRU of claim 6 , wherein the processor is configured to adjust the WTRU transmission power for commands on the E-RGCH for the monitored cells by using the cell offset for each cell.

8. The WTRU of claim 6 , wherein the hysteresis threshold comprises the signal quality of the serving cell added to an offset.

Assignees

• Marinier Paul
• Pani Diana
• Cave Christopher
• Interdigital Patent Holdings Inc

Inventors

• Marinier Paul
• Pani Diana
• Cave Christopher

Classifications

• H04W72/542

  using measured or perceived quality · CPC title

• H04W72/541 Primary

  using the level of interference · CPC title

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W72/082 Primary

  Electricity · mapped topic

• H04W28/048

  Electricity · mapped topic