Weighted open loop power control

• US 7,120,189 B2
• Filed: 05/16/2005
• Issued: 10/10/2006
• Est. Priority Date: 03/21/2000
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Shin, Sung-Hyuk, Zeira, Ariela
• Primary Examiner(s): Ghebretinsae, Temesghen
• Application Number:
  US11/130,591
• Publication Number:
  US 20050220176A1
• Time in Patent Office: 512 Days
• Field of Search: 375/130, 375/140, 375/146, 375/295, 370/342, 370/252, 370/347, 370/318, 455/69, 455/522
• US Class Current: 375/130
• CPC Class Codes: H04B 2201/709709 Methods of preventing interference
• CPC Class Codes: H04W 52/10 Open loop power control
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/246 where the output power of a terminal is based on a path parameter calculated in said terminal
• CPC Class Codes: H04W 52/248 where transmission power control commands are generated based on a path parameter

Abstract

A base station transmits a reference signal. The base station receives a communication. The received communication has a transmission power level set by measuring an interference level; determining the pathloss estimate using the reference signal; determining a long term average of pathloss estimates; multiplying a first weighting factor, α, by the determined pathloss estimate, producing a weighted pathloss estimate; multiplying (1−α) to the determined long term average of pathloss estimates, producing a weighted long term pathloss estimate; and determining the transmission power level by adding the weighted pathloss estimate to the weighted long term pathloss estimate to the measured interference level to a target signal to interference ratio to a constant value.

Claims

1. A method for a base station in a wireless time division duplex communication system using code division multiple access, the method comprising:

transmitting a reference signal; and

receiving a communication, the received communication having a transmission power level set by measuring an interference level;

determining the pathloss estimate using the reference signal;

determining a long term average of pathloss estimates;

multiplying a first weighting factor, α

, by the determined pathloss estimate, producing a weighted pathloss estimate;

multiplying (1−

α

) to the determined long term average of pathloss estimates, producing a weighted long term pathloss estimate; and

determining the transmission power level by adding the weighted pathloss estimate to the weighted long term pathloss estimate to the measured interference level to a target signal to interference ratio to a constant value.

2. The method of claim 1 wherein the first weighting factor represents a quality of the pathloss estimtate.

3. The method of claim 1 wherein the determining the pathloss estimate is by subtracting a received power level of the reference signal from a transmit power level signaled on a broadcast channel, further comprising transmitting the broadcast channel.

4. A time division duplex/code division multiple access base station comprising:

a reference channel data generator and an antenna for transmitting a reference signal; and

the antenna for receiving a communication, the received communication having a transmission power level set by measuring an interference level;

determining the pathloss estimate using the reference signal;

determining a long term average of pathloss estimates;

multiplying a first weighting factor, α

, by the determined pathloss estimate, producing a weighted pathloss estimate;

multiplying (1−

α

) to the determined long term average of pathloss estimates, producing a weighted long term pathloss estimate; and

determining the transmission power level by adding the weighted pathloss estimate to the weighted long term pathloss estimate to the measured interference level to a target signal to interference ratio to a constant value.

5. The time division duplex/code division multiple access base station of claim 4 wherein the first weighting factor represents a quality of the pathloss estimate.

6. The time division duplex/code division multiple access base station of claim 4 wherein the determining the pathloss estimate is by subtracting a received power level of the reference signal from a transmit power level signaled on a broadcast channel, the antenna for transmitting the broadcast channel.

7. A time division duplex/code division multiple access user equipment comprising:

means for transmitting a reference signal; and

means for receiving a communication, the received communication having a transmission power level set by measuring an interference level;

determining the pathloss estimate using the reference signal;

determining a long term average of pathloss estimates;

multiplying a first weighting factor, α

, by the determined pathloss estimate, producing a weighted pathloss estimate;

multiplying (1−

α

) to the determined long term average of pathloss estimates, producing a weighted long term pathloss estimate; and

determining the transmission power level by adding the weighted pathloss estimate to the weighted long term pathloss estimate to the measured interference level to a target signal to interference ratio to a constant value.

8. The time division duplex/code division multiple access base station of claim 7 wherein the first weighting factor represents a quality of the pathloss estimate.

9. The time division duplex/code division multiple access base station of claim 7 wherein the determining the pathloss estimate is by subtracting a received power level of the reference signal from a transmit power level signaled on a broadcast channel, the means for transmitting for transmitting the broadcast channel.