Prevention of unnecessary hand-over caused by fading

A method of controlling hand-over to change connections between a radio communication terminal and a plurality of radio communication base stations for radio communication, the method comprising the steps of:

• (a) when one of the radio communication base stations receives from the radio communication terminal information about the qualities of signals received from the plurality of radio communication base stations and executes a first hand-over operation, on the basis of said information, to change or finish connections between the radio communication terminal and at least part of the radio communication base stations for radio communication, storing identifiers of radio communication base station(s), with which the radio communication terminal has finished radio communication, and information about the qualities of signals received from said radio communication base station(s) when the radio communication terminal has finished radio communication with said radio communication base station(s);
• (b) when one of the radio communication base stations receives from the radio communication terminal information about the qualities of signals received from the radio communication base stations and executes a second hand-over operation, on the basis of said information, to change connections between the radio communication terminal and at least part of the radio communication base stations for radio communication, determining whether or not a particular radio communication base station with which the radio communication terminal is about to start communicating, was previously put in radio communication with the radio communication terminal, based on the presence or absence of the identifier of the particular radio communication base station;
• (c) if the one of the radio communication base stations has determined at step (b) that the particular radio communication base station was previously put in radio communication with the radio communication terminal, comparing the quality of a first signal currently received from the particular radio communication base station with the quality of a second signal received from the particular radio communication base station stored at step (a) when the radio communication terminal has finished the radio communication with the particular radio communication base station;
• and
• (d) if the quality of the first signal is higher than the quality of the second signal by a predetermined level or more, executing said second hand-over operation in the radio communication terminal to start radio communication with the particular radio communication base station.

A computer program for enabling a computer to perform control of hand-over to change connections between a radio communication terminal and a plurality of radio communication base stations for radio communication, the computer program comprising the software instructions of:

• (a) when the radio communication terminal executes a first hand-over operation, on the basis of the qualities of signals received from the radio communication base stations, to change or finish connections between the radio communication terminal and at least part of the radio communication base stations for radio communication, storing identifiers of radio communication base station(s), with which the radio communication terminal finished radio communication, and information about the qualities of signals received from said radio communication base station(s) when the radio communication terminal finished radio communication with said radio communication base station(s);
• (b) when the radio communication terminal executes a second hand-over operation, on the basis of the qualities of signals received from the radio communication base stations, to change connections between the radio communication terminal and at least part of the radio communication base stations for radio communication, determining whether or not a particular radio communication base station with which the radio communication terminal is about to start communicating, was previously put in radio communication with the radio communication terminal, based on the presence or absence of the identifier of the particular radio communication base station;
• (c) if the radio communication terminal has determined by software instruction (b) that the particular radio communication base station was previously put in radio communication with the radio communication terminal, comparing the quality of a first signal currently received from the particular radio communication base station with the quality of a second signal received from the particular radio communication base station stored by software instruction (a) when the radio communication terminal finished the radio communication with the particular radio communication base station;
• and
• (d) if the quality of the first signal is higher than the quality of the second signal by a predetermined level or more, executing said second hand-over operation in the radio communication terminal to start radio communication with the particular radio communication base station.

A computer program for enabling a computer to perform control hand-over to change connections between a radio communication terminal and a plurality of radio communication base stations for radio communication, the computer program comprising the software instructions of:

• (a) when one of the radio communication base stations receives from the radio communication terminal information about the qualities of signals received from the plurality of radio communication base stations and executes a first hand-over operation, on the basis of said information, to change or finish connections between the radio communication terminal and at least part of the radio communication base stations for radio communication, storing identifiers of radio communication base station(s), with which the radio communication terminal has finished radio communication, and information about the qualities of signals received from said radio communication base station(s) when the radio communication terminal has finished radio communication with said radio communication base station(s);
• (b) when one of the radio communication base stations receives from the radio communication terminal information about the qualities of signals received from the radio communication base stations and executes a second hand-over operation, on the basis of said information, to change connections between the radio communication terminal and at least part of the radio communication base stations for radio communication, determining whether or not a particular radio communication base station with which the radio communication terminal is about to start communicating, was previously put in radio communication with the radio communication terminal, based on the presence or absence of the identifier of the particular radio communication base station;
• (c) if the one of the radio communication base stations has determined by software instruction (b) that the particular radio communication base station was previously put in radio communication with the radio communication terminal, comparing the quality of a first signal currently received from the particular radio communication base station with the quality of a second signal received from the particular radio communication base station stored by software instruction (a) when the radio communication terminal has finished the radio communication with the particular radio communication base station;
• and
• (d) if the quality of the first signal is higher than the quality of the second signal by a predetermined level or more, executing said second hand-over operation in the radio communication terminal to start radio communication with the particular radio communication base station.

A radio communication terminal connectable with a plurality of radio communication base stations for radio communication, the terminal comprising:

• first means, when executing a first hand-over operation, on the basis of the qualities of signals received from the radio communication base stations, to change or finish connections of the radio communication terminal with at least part of the radio communication base stations for radio communication, for storing identifiers of radio communication base station(s), with which the radio communication terminal finished radio communication, and information about the qualities of signals received from said radio communication base station(s) when the radio communication terminal finished radio communication with said radio communication base station(s);
• second means, when executing a second hand-over operation, on the basis of the qualities of signals received from the radio communication base stations, to change connections of the radio communication terminal with at least part of the radio communication base stations for radio communication, for determining whether or not a particular radio communication base station with which the radio communication terminal is about to start communicating, was previously put in radio communication with the radio communication terminal, based on the presence or absence of the identifier of the particular radio communication base station;
• third means, if said second means has determined that the particular radio communication base station was previously put in radio communication with the radio communication terminal, for comparing the quality of a first signal currently received from the particular radio communication base station with the quality of a second signal received from the particular radio communication base station stored in said first means when the radio communication terminal finished the radio communication with the particular radio communication base station;
• and
• fourth means, if the quality of the first signal is higher than the quality of the second signal by a predetermined level or more, for executing said second hand-over operation in the radio communication terminal to start radio communication with the particular radio communication base station.

A radio communication base station connectable with a radio communication terminal for radio communication, the station comprising:

• first means for, when receiving from the radio communication terminal information about the qualities of signals received from a plurality of radio communication base stations including said radio communication base station and executing a first hand-over operation, on the basis of the information, to change or finish connections of the radio communication terminal with at least part of the radio communication base stations for radio communication, storing identifiers of radio communication base station(s), with which the radio communication terminal finished radio communication, and information about the qualities of signals received from said radio communication base station(s) when the radio communication terminal finished radio communication with said radio communication base station(s);
• second means, when receiving from the radio communication terminal information about the qualities of signals received from a plurality of radio communication base stations including said radio base stations and executing said second hand-over operation, on the basis of the information, to change connections of the radio communication terminal with at least part of the radio communication base stations for radio communication, determining whether or not a particular radio communication base station with which the radio communication terminal is about to start communicating, was previously put in radio communication with the radio communication terminal, based on the presence or absence of the identifier of the particular radio communication base station;
• third means for, if said second means has determined that the particular radio communication base station was previously put in radio communication with the radio communication terminal, comparing the quality of a first signal currently received from the particular radio communication base station with the quality of a second signal received from the particular radio communication base station stored in said first means when the radio communication terminal finished radio communication with the particular radio communication base station;
• and
• fourth means, if the quality of the first signal is higher than the quality of the second signal by a predetermined level or more, executing the second hand-over operation in the radio communication terminal to start radio communication with the particular radio communication base station.