User equipment using combined closed loop/open loop power control

• US 20040196890A1
• Filed: 04/26/2004
• Published: 10/07/2004
• Est. Priority Date: 03/21/2000
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Shin, Sung-Hyuk, Zeira, Ariela, Ozluturk, Fatih M.
• Granted Patent: US 6,928,102 B2
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: H04B 2201/709709 Methods of preventing interference
• CPC Class Codes: H04W 52/08 Closed loop power control
• 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 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/248 where transmission power control commands are generated based on a path parameter
• CPC Class Codes: H04W 52/265 taking into account the quality of service QoS
• CPC Class Codes: H04W 52/54 Signalisation aspects of the TPC commands, e.g. frame structure
• CPC Class Codes: H04W 52/60 using different transmission rates for TPC commands

Abstract

A spread spectrum time division duplex user equipment uses frames with time slots for communication. It receives power commands and receives a first communication having a transmission power level in a first time slot. It measures a power level of the first communication as received and determines a pathloss estimate based on in part the measured received first communication power level and the first communication transmission power level. The user equipment sets a transmission power level for a second communication in a second time slot from the user equipment based on in part the pathloss estimate weighted by a quality factor and adjusted by the power commands.

Claims

1. A spread spectrum time division duplex user equipment, the user equipment using frames with time slots for communication, receiving power commands and receiving a first communication having a transmission power level in a first time slot, measuring a power level of the first communication as received and determining a pathloss estimate based on in part the measured received first communication power level and the first communication transmission power level, the user equipment comprising:

means for setting a transmission power level for a second communication in a second time slot from the user equipment based on in part the pathloss estimate weighted by a quality factor and adjusted by the power commands.

2. The user equipment of claim 1 wherein the setting means sets the transmission power level based on in part a desired received power level, a closed loop factor and an open loop factor, the closed loop factor is based on in part the received power commands and the open loop factor is based on in part the pathloss estimate weighted by the quality factor.

3. The user equipment of claim 1 wherein the setting means sets the transmission power level based on in part a desired received power level at the first station and a combined closed loop/open loop factor, the combined closed loop/open loop factor is based on in part the received power commands and the path loss estimate weighted by the quality factor.

4. The user equipment of claim 2 wherein the closed loop factor is updated for each received power command.

5. The user equipment of claim 3 wherein the combined factor is updated for each received power command.

6. The user equipment of claim 2 wherein the desired received power level is based on in part a target signal to interference ratio and a measured interference level.

7. The user equipment of claim 3 wherein the desired received power level is based on in part a target signal to interference ratio and a measured interference level.