PILOT SIGNAL TRANSMISSION IN A RADIO COMMUNICATION SYSTEM

• US 20100022266A1
• Filed: 09/27/2007
• Published: 01/28/2010
• Est. Priority Date: 01/24/2007
• Status: Abandoned Application

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Villier, Eric R., Lopes, Luis
• Application Number:
  US12/518,290
• Publication Number:
  US 20100022266A1
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04W 52/0232 according to average transmission signal activity
• CPC Class Codes: H04W 52/143 Downlink power control
• 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 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

An access point for a radio communication system transmits a pilot signal. The access point can operate in different modes with the pilot signal transmit power being controlled differently. A mode processor (105) controls a pilot signal controller (103) such that when in a first mode the access point is arranged to vary a pilot signal transmit power in accordance with a first transmit power profile. Another mode processor (107) controls the pilot signal transmit power in accordance with a second profile in a second mode. The transmit power may be constant during the second mode. A transition processor (111) is arranged to transition the access point from the first mode to the second mode in response to receiving an access request for a remote station.

Claims

1. An access point for a radio communication system, the access point comprising:

means for operating in a first mode wherein the access point is arranged to vary a pilot signal transmit power in accordance with a first transmit power profile;

means for operating in a second mode wherein the access point is arranged to control the pilot signal transmit power in accordance with a second transmit power profile; and

means for transitioning the access point from the first mode to the second mode in response to receiving an access request for a remote station.

2. The access point of claim 1 wherein the first transmit power profile corresponds to a power variation between a minimum transmit power level and a maximum transmit power level, the maximum transmit power level corresponding to a coverage area of the cell.

3. The access point of claim 1 wherein the second transmit power profile corresponds to a substantially constant transmit power level that depends on previous power controlled pilot signal transmit power levels.

4. The access point of claim 1 further comprising means for transitioning the access point from the second mode to the first mode in response to a detection of an access failure for the remote station.

5. The access point of claim 1 wherein the access point is arranged to operate in the first mode when no remote station is supported by the access point.

6. The access point of claim 1 further comprising:

means for operating in a third mode wherein the access point is arranged to set the pilot signal transmit power in response to a power control loop including the remote station; and

means for transitioning to the third mode upon completion of an access procedure for the remote station.

7. The access point of claim 6 further comprising means for transitioning from the third mode to the second mode in response to receiving an access request for a second remote station.

8. The access point of claim 6 wherein the power control loop involves a plurality of remote stations and the access point is arranged to reduce the pilot signal transmit power only if all involved remote stations request a power reduction.

9. The access point of claim 6 further comprising means for transitioning from the third mode to the first mode in response to a detachment of the remote station.

10. A method of operation for an access point for a radio communication system, the method comprising:

operating in a first mode wherein a pilot signal transmit power is varied in accordance with a first transmit power profile;

operating in a second mode wherein the pilot signal transmit power is controlled in accordance with a second transmit power profile; and

transitioning the access point from the first mode to the second mode in response to receiving an access request for a remote station.