WEIGHTED OPEN LOOP POWER CONTROL SYSTEM

• US 20070025423A1
• Filed: 10/06/2006
• Published: 02/01/2007
• Est. Priority Date: 03/21/2000
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Shin, Sung-Hyuk, Zeira, Ariela
• Granted Patent: US 7,289,550 B2
• Time in Patent Office: Days
• US Class Current: 375/141
• 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 weighted open loop power control system for controlling transmission power levels using a spread spectrum time division duplex (TDD) technique having frames with timeslots for communication comprises a receiver and a transmitter. The receiver includes a reference channel data generator, a spreading and training sequence insertion device, an amplifier, a summer, a modulator, and an antenna. The transmitter includes a demodulator configured to receive a transmitted signal from the receiver, a channel estimation device, a data estimation device, and a weighted open loop power controller. The weighted open loop power controller includes a power measurement device, a pathloss estimation device configured to receive an interpreted power level from the data estimation device and estimate the pathloss and update a long term average of the pathloss, a quality measurement device, and a transmit power calculation device for determining the transmitter'"'"'s power level and to control the receiver'"'"'s amplifier.

Claims

1. A weighted open loop power control system for controlling transmission power levels using a spread spectrum time division duplex (TDD) technique having frames with timeslots for communication, the system comprising:

a receiver unit comprising;

a reference channel data generator configured to generate a reference channel data;

a spreading and training sequence insertion device configured to generate a communication burst by spreading the reference channel data and time-multiplex the reference channel data with a training sequence in appropriate timeslots;

an amplifier, in communication with the spreading and training sequence insertion device, the amplifier configured to amplify the communication burst;

a summer, configured to receive the amplified communication burst and sum the amplified communication burst with other communication bursts;

a modulator, configured to receive and modulate the summed amplified communication burst;

an antenna configured to transmit the modulated communication burst and information relating to the transmitted power level, over an air interface; and

a transmitter unit comprising;

a demodulator configured to receive the transmitted modulated communication burst and generate a baseband signal;

a channel estimation device configured to receive the baseband signal and extract channel information from the baseband signal;

a data estimation device configured to interpret the power level of the communication burst;

a weighted open loop power controller, said weighted open loop power controller comprising;

a power measurement device for receiving the extracted channel information from the channel estimation device, a pathloss estimation device configured to receive the interpreted power level from the data estimation device and estimate the pathloss (L) and update a long term average of the pathloss (L0) between the receiver unit and the transmitter unit, a quality measurement device to determine the quality of the estimated pathloss and weight the estimated pathloss by a weighting factor (α

), and a transmit power calculation device, wherein the transmit power calculation device for determining the transmitter'"'"'s unit power level and to control the receiver'"'"'s unit amplifier.

2. The system of claim 1, wherein the transmit power calculation device determines the transmitter'"'"'s unit power level by adding a desired receiver power level to α

(L−

L0) to L0 to a constant value.