Communication terminal out of range determination method, wireless communication system switching method and communication terminal

• US 20040242218A1
• Filed: 05/14/2004
• Published: 12/02/2004
• Est. Priority Date: 05/29/2003
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Saito, Masahiro
• Granted Patent: US 7,801,516 B2
• Time in Patent Office: Days
• US Class Current: 455/421
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/326 by proximity to another entity
• CPC Class Codes: H04W 36/362 Conditional handover
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 76/20 Manipulation of established connections

Abstract

There is provided a communication terminal out of range determination method, a wireless communication system switching method and a communication terminal, capable of determining accurately whether or not a communication terminal is out of range. Determining whether or not the communication terminal is out of range is based on a transmission level of a transmission signal from the communication terminal to a base station.

Claims

1. A communication terminal out of range determination method comprising the step of determining whether or not a communication terminal is out of range, based on a level of transmission signals from the communication terminal to a base station.

2. A communication terminal out of range determination method comprising the step of determining that a communication terminal, which controls a transmission level based on control information received from a base station so that a level of signals received by the base station becomes a reference level, is out of range, when the communication terminal receives the control information from the base station, despite the communication terminal transmitting at a level which exceeds a predetermined threshold.

3. A wireless communication system switching method in a communication terminal capable of connecting to a plurality of different wireless communication systems comprising the steps of:

determining whether or not the communication terminal is out of range based on a level of transmission signals from the communication terminal to a base station, and

if determined to be out of range, beginning preparation for connecting to a different wireless communication system from the wireless communication system to which the communication terminal is connected.

4. A communication terminal comprising:

a transmission unit which transmits signals to a base station;

a detection unit which detects a level of the signals transmitted by the transmission unit; and

a determination unit which determines whether or not the communication terminal is out of range based on the level of the signals detected by the detection unit.

5. A communication terminal comprising:

a transmission unit which transmits signals to a base station;

a control unit which controls a level of the signals transmitted by the transmission unit based on control information received from the base station so that a level of signals received by the base station becomes a reference level;

a storage unit which stores a predetermined threshold value; and

a determination unit which determines that the communication terminal is out of range when the control information is received from the base station despite the transmission unit transmitting at a level which exceeds the threshold value.

6. A communication terminal comprising:

a communication unit capable of connecting to a plurality of different wireless communication systems;

a detection unit which detects a level of signals transmitted by the communication terminal;

a determination unit which determines whether or not the communication terminal is out of range based on the level of the signals; and

a switching unit which, if the determination unit has determined that the communication terminal is out of range, begins preparation for connecting to a different wireless communication system from the wireless communication system to which the communication terminal is connected.