Mobile communication terminal

• US 20080004020A1
• Filed: 04/03/2006
• Published: 01/03/2008
• Est. Priority Date: 11/10/2005
• Status: Active Grant

• Current Assignee: Godo Kaisha IP Bridge 1 (IP Bridge, Inc.)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Yasuda, Chikara
• Granted Patent: US 7,627,318 B2
• Time in Patent Office: Days
• US Class Current: 455/436
• CPC Class Codes: H04W 36/0085 Hand-off measurements
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 36/302 due to low signal strength

Abstract

A mobile communication terminal has a function of communicating with two types of base stations, for example, one base station belongs to the GSM system and another base station belongs to the WCDMA system. The mobile communication terminal receives radio signal from a communicating base station and a neighboring base station, and measures received radio signal quality. Then, judging whether hand-over process is to be executed or not based upon comparison of the measured received radio signal quality and relationship between the received radio signal quality and data throughput.

Claims

1. A mobile communication terminal capable of communicating with a base station which belongs to one of two communication system, comprising:

receiving means for receiving radio signal from the base station;

measuring means for measuring received radio signal quality;

a storage unit which stores the relationship between received radio signal quality and data throughput; and

hand-over judging means for judging whether the hand-over process is to be executed based upon the received radio signal quality measured by the measuring means and the relationship stored in the storage unit.

2. The mobile communication terminal according to claim 1, wherein the measuring means measures the received signal quality of the communicating base station and the received signal quality of a neighboring base station, and the hand-over judging means judges the hand-over process is to be executed if the throughput of the neighboring base station is higher than that of the communicating base station.

3. The mobile communication terminal according to claim 1, wherein the received signal quality measured by the measuring means is a received signal strength indicator.

4. The mobile communication terminal according to claim 1, further comprising a control unit which has a function for transmitting and receiving electronic mail via the base station and a function for receiving and reproducing a content received from a contents server via the base station;

and

the hand-over judging means judges whether hand-over process is to be executed based upon the relationship stored in the storage unit if the electronic mail function is activated, and judges whether the hand-over process is to be executed base on the received signal quality measured by the measuring means.

5. The mobile communication terminal according to claim 1, wherein the mobile communication terminal is capable of communicating with a base station belongs to the GSM standard and a base station belongs to the WCDMA standard.

6. A mobile communication terminal capable of communicating with a base station which belongs to one of two communication system, comprising:

receiving means for receiving radio signal from the base station;

measuring means for measuring error rate of the received radio signal received by the receiving means;

a storage unit which stores the relationship between error rate of the received radio signal and data throughput; and

hand-over judging means for judging whether the hand-over process is to be executed based upon the received radio signal quality measured by the measuring means and the relationship stored in the storage unit.

7. The mobile communication terminal according to claim 6, wherein the measuring means measures the error rate of the received signal from the communicating base station and the error rate of the received signal from a neighboring base station, and the hand-over judging means judges the hand-over process is to be executed if the throughput of the neighboring base station is higher than that of the communicating base station.

8. The mobile communication terminal according to claim 6, further comprising a control unit which has a function for transmitting and receiving electronic mail via the base station and a function for receiving and reproducing a content received from a contents server via the base station;

and

the hand-over judging means judges whether hand-over process is to be executed based upon the relationship stored in the storage unit if the electronic mail function is activated, and judges whether the hand-over process is to be executed base on the error rate of the received signal measured by the measuring means.

9. A mobile communication terminal selectively connectable to first base station belongs to first communication system and second base station belongs to second communication system, comprising:

receiving means for receiving radio signal from the first and second base stations;

measuring means for measuring received radio signal quality;

a storage unit which stores the relationship between received signal quality and data throughput; and

hand-over judging means for judging whether the hand-over process from the firs base station to the second base station is to be executed based upon the received radio signal quality measured by the measuring means and the relationship stored in the storage unit.

10. The mobile communication terminal according to claim 9, wherein the received signal quality measured by the measuring means is a received signal strength indicator.

11. The mobile communication terminal according to claim 9, wherein the first communication system is pursuant to the GSM standard and the second communication system is pursuant to the WCDMA standard.