User equipment utilizing weighted open loop power control

• US 6,845,122 B2
• Filed: 05/28/2003
• Issued: 01/18/2005
• Est. Priority Date: 03/21/2000
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Shin, Sung-Hyuk, Zeira, Ariela
• Primary Examiner(s): Ghebretinsae, Temesghen
• Application Number:
  US10/446,539
• Publication Number:
  US 20030193916A1
• Time in Patent Office: 601 Days
• Field of Search: 375/130, 375/140, 375/146, 370/342, 370/252, 455/522, 455/69
• 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 user equipment (UE) employs weighted open loop power control by receiving a communication and measuring its received power level. Based on, in part, the received communication'"'"'s power level and the communication'"'"'s transmission power level, a path loss estimate is determined. A quality of the path loss estimate is also determined. The transmission power level for a communication from the UE is based, in part, on weighting the path loss estimate in response to the estimate'"'"'s quality.

Claims

1. A user equipment (UE) employing a spread spectrum time division duplex technique using frames with time slots for communication, comprising:

means for receiving, in a first time slot, a first communication having a power level;

means for measuring a power level of the first communication;

means for determining a path loss estimate based in part on the measured power level and the received power level;

means for determining a long term path loss estimate based on prior path loss estimates;

means for setting a transmission power level for a second communication in a second time slot based in part on the path loss estimate weighted by a first factor and the long term path loss estimate weighted by a second factor, wherein the first and second factors are a function of a time separation of the first and second time slots; and

means for transmitting the second communication in the second time slot at the set transmission power level.

2. The user equipment of claim 1 wherein said means for determining the long term path loss estimate is responsive at least in part upon an average of path loss estimates of received communications.

3. A user equipment having its transmission power level controlled and using a spread spectrum time division duplex technique using frames with time slots for communication comprising:

antenna for receiving, during a first time slot, a first communication and transmitting an amplified second communication in a second time slot;

a power measurement device responsive to channel information for producing a measurement of a received power level of the first communication;

a pathloss estimation device responsive to the measured received power level for producing a pathloss estimate for the first communication;

a quality measurement device for producing a quality measurement based at least in part upon a time separation of the first time slot and a second time slot;

a transmit power calculation device responsive to the pathloss estimation and the quality measurement for producing a power control signal based at least in part upon the path loss estimate weighted by a first factor and a long term pathloss estimate weighted by a second factor, wherein the first and second factors are based in part on the quality measurement; and

an amplifier responsive to the power control signal and a second communication to be transmitted in the second time slot for amplifying the second communication as a function of the power control signal to produce the amplified second communication.