US 7,010,320 B2 · Transmission power control method, base station, mobile station and mobile communication system

Abstract

This invention is to prevent deterioration in communication quality of closed loop transmission power control, which may occur when the change in transmission power cannot keep up with a sudden change in the state of a transmission path. Transmission power control command extractor 4 extracts a transmission power control command from the uplink signal that has been received by receiver 2. Mobile position predictor 7 predicts the future position of the mobile station from its present position as recognized by mobile position recognizer 5 and from its present rate of movement as recognized by mobile velocity recognizer 6. Database 8 records the state of the downlink transmission path as a function of mobile position. Transmission power controller 9 looks up database 8 on the basis of the predicted future position of the mobile station and controls the downlink transmission power of base station BS on the basis of (i) the result of this lookup, and (ii) the transmission power control command. Transmitter 11 transmits at the downlink transmission power that has been instructed by transmission power controller 9.

Claims12

Dependent claims

A base station which uses uplink transmission power control commands transmitted from the base station via a downlink to control the uplink transmission power of a mobile station in such manner that the uplink receiving state at this base station becomes good:

which is characterized by comprising:
a receiver for receiving uplink radio signals that have been transmitted via the uplink;
an uplink receiving state estimator for estimating the receiving state of the uplink from the received uplink signal;
a mobile position recognizer for recognizing the present position of the mobile station from the received uplink signal;
a mobile velocity recognizer for recognizing the present rate of movement of the mobile station from the received uplink signal;
a mobile position predictor for predicting the future position of the mobile station from its present position and present rate of movement;
a database in which the state of the uplink transmission path has been recorded as a function of mobile position;
an uplink transmission power control command generator for looking up the database on the basis of the predicted future position of the mobile station, and for generating an uplink transmission power control command for controlling the uplink transmission power of the mobile station on the basis of (i) the future state of the uplink transmission path obtained as a result of the lookup, and (ii) the aforementioned estimated uplink receiving state;
a mixer for outputting the mixed signal obtained by mixing the downlink data with the aforementioned generated uplink transmission power control command;
and
a transmitter for transmitting the mixed signal.

8 more elements

A mobile station which uses uplink transmission power control commands transmitted from a base station via a downlink to control its uplink transmission power in such manner that the uplink receiving state at the base station becomes good:

which is characterized by comprising:
a receiver for receiving downlink radio signals that have been transmitted via the downlink;
an uplink transmission power control command extractor for extracting the aforementioned uplink transmission power control commands from the received downlink signal;
a mobile position recognizer for recognizing the present position of the mobile station;
a mobile velocity recognizer for recognizing the present rate of movement of the mobile station;
a mobile position predictor for predicting the future position of the mobile station from its present position and present rate of movement;
a database in which the state of the uplink transmission path has been recorded as a function of mobile position;
an uplink transmission power controller for looking up the database on the basis of the predicted future position of the mobile station, and for controlling the uplink transmission power of the mobile station on the basis of (i) the future state of the uplink transmission path obtained as a result of the lookup, and (ii) the aforementioned uplink transmission power control commands;
and
a transmitter for transmitting at the uplink transmission power instructed by the uplink transmission power controller.

7 more elements

Dependencies are inferred from the claim text.

Transmission power control method, base station, mobile station and mobile communication system

Life of this patent

Transmission power control method, base station, mobile station and mobile communication system

Life of this patent

Abstract

Claims12