POWER CONTROL OF POINT TO MULTIPOINT PHYSICAL CHANNELS

• US 20100197341A1
• Filed: 04/12/2010
• Published: 08/05/2010
• Est. Priority Date: 08/01/2002
• Status: Active Grant

• Current Assignee: Pantech Wireless, LLC (Ideahub, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Terry, Stephen E.
• Granted Patent: US 8,606,282 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04W 52/06 TPC algorithms
• CPC Class Codes: H04W 52/08 Closed loop power control
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/247 where the output power of a terminal is based on a path parameter sent by another terminal
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 52/28 using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non transmission
• CPC Class Codes: H04W 52/322 Power control of broadcast channels
• CPC Class Codes: H04W 52/327 Power control of multicast channels
• CPC Class Codes: H04W 72/30 Resource management for broadcast services

Abstract

A method and apparatus are used to determine an efficient transmit power for point to multipoint (PtM) transmissions by maintaining a database at a base station which specifies which of a plurality of wireless transmit/receive units (WTRUs) are members of each PtM group. The transmit power of each WTRU'"'"'s downlink dedicated channel is adjusted to the minimum required power necessary and the PtM transmit power for each PtM group is set such that the PtM transmit power of a PtM group is equal to the greatest of a WTRU in the PtM group plus a PtM power offset.

Claims

1. A base station configured to transmit point to multipoint (PtM) channels in wireless communications, the base station comprising:

a receiver configured to receive transmit power control (TPC) commands from a plurality of wireless transmit receive units (WTRUs);

a processor configured to;

categorize each WTRU of the plurality of WTRUs according to the TPC commands and a database created on the basis of an association of a WTRU with a Ptm channel, wherein the database includes groups of WTRUs from the plurality of WTRUs that are associated with each PtM channel;

adjust a transmit power level of a downlink (DL) channel associated with each WTRU of the plurality of WTRUs;

set a transmission power level for each of the groups of WTRUs wherein the transmission power level for a PtM channel equals a maximum transmission power level required for a WTRU of the group adjusted by an offset parameter.

a PtM transmitter configured to produce a PtM channel with the transmission power level;

an amplifier configured to control the transmission power level of the PtM channel; and

an antenna configured to radiate the PtM channel from a wireless interface.

2. The base station of claim 1, wherein the processor is configured to use TPC commands to adjust the transmit power level of each WTRUs'"'"' DL channel at a minimum required power level to achieve a Quality of Service (QoS) associated with each of the WTRUs.

3. The base station of claim 1, wherein the offset parameter is an adjustment to correct for Quality of Service (QoS) and coding rate differences between the DL dedicated channel and the PtM channel.

4. The base station of claim 1, wherein the processor is further configured to iteratively adjust the transmission power level of the PtM channel based upon a slot basis, a radio frame basis, or a transmission time interval (TTI) basis.

5. The base station of claim 1, wherein offset parameter adjusts power of a PtM channel in a configured step basis in decibels (dB).

6. The base station of claim 1, wherein the processor is further configured to determine a transmission power for a common channel is determined by multiplying an operator controlled factor with a power ratio and the transmission power level.

7. The base station of claim 6, wherein the ratio is a signal-to-interference ratio and the ratio is replaced by a pathloss factor.

8. A method for transmission of point to multipoint (PtM) channels in wireless communications, the method comprising:

receiving transmit power control (TPC) commands from a plurality of wireless transmit receive units (WTRUs);

categorizing each WTRU of the plurality of WTRUs according to the TPC commands and a database created on the basis of an association of a WTRU with a Ptm channel, wherein the database includes groups of WTRUs from the plurality of WTRUs that are associated with each PtM channel;

adjusting a transmit power level of a downlink (DL) channel associated with each WTRU of the plurality of WTRUs;

setting a transmission power level for each of the groups of WTRUs wherein the transmission power level for a PtM channel equals a maximum transmission power level required for a WTRU of the group adjusted by an offset parameter.

producing a PtM channel with the transmission power level;

controlling the transmission power level of the PtM channel; and

radiating the PtM channel from a wireless interface.

9. The method of claim 8, wherein the TPC commands are used to adjust the transmit power level of each WTRUs'"'"' DL channel at a minimum required power level to achieve a Quality of Service (QoS) associated with each of the WTRUs.

10. The method of claim 8, wherein the offset parameter is an adjustment to correct for Quality of Service (QoS) and coding rate differences between the DL dedicated channel and the PtM channel.

11. The method of claim 8, the transmission power level of the PtM channel is iteratively adjusted based upon a slot basis, a radio frame basis, or a transmission time interval (TTI) basis.

12. The method of claim 8, wherein offset parameter adjusts power of a PtM channel in a configured step basis in decibels (dB).

13. The method of claim 8 further comprising a determining a transmission power for a common channel by multiplying an operator controlled factor with a power ratio and the transmission power level.

14. The method of claim 8, wherein the ratio is a signal-to-interference ratio and the ratio is replaced by a pathloss factor.