Short range wireless communication system, portable terminal apparatus, and wireless communication apparatus

• US 20060003700A1
• Filed: 07/01/2005
• Published: 01/05/2006
• Est. Priority Date: 07/05/2004
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Ericsson Mobile Communications Japan Incorporated (Sony Group Corp.)
• Inventors: Yoshimura, Osamu, Itoh, Katsutoshi, Itagaki, Takeshi, Yasuda, Mitsuyoshi, Yokoshi, Minoru, Natori, Makoto
• Granted Patent: US 7,336,929 B2
• Time in Patent Office: Days
• US Class Current: 455/41.200
• CPC Class Codes: G08B 13/1427 with transmitter-receiver for distance detection
• CPC Class Codes: H04B 1/3805 with built-in auxiliary receivers

Abstract

A portable terminal monitors a signal level of a short-range wireless signal from a wireless communication apparatus. If the signal level drops so low that a state of connection for short-range wireless communications cannot be maintained between the two apparatuses, use of predetermined functions of the portable terminal is limited. A short-range wireless communication facility of the portable terminal and the wireless communication apparatus move into a particular operation mode if communications do not occur therebetween at least for a predetermined time period. In monitoring the signal level of the wireless signal from the wireless communication apparatus in the particular operation mode, the portable terminal reduces a response speed at which to detect a signal level change. This causes the wireless communication apparatus to delay issuing a request for an increase in transmission power, thereby reducing unevenness of the working distance at which to alert a user to the unusual distance traveled between the two apparatuses or beyond which to limit the use of some functions of the portable terminal.

Claims

1. A short-range wireless communication system comprising a portable terminal apparatus having a short-range wireless communication facility, and a wireless communication apparatus capable of wirelessly communicating with said portable terminal apparatus at close range, one of the two apparatuses monitoring a signal level of a wireless signal transmitted by the other apparatus so that if said signal level drops below a predetermined threshold, said one apparatus requesting said other apparatus to increase transmission power, wherein

said portable terminal apparatus limits use of predetermined functions thereof if said signal level of said wireless signal from said wireless communication apparatus at close range drops so low that a state of short-range wireless connection with said wireless communication apparatus cannot be maintained;

said short-range wireless communication facility of said portable terminal apparatus and said wireless communication apparatus move into a particular operation mode if short-range wireless communications do not take place therebetween at least for a predetermined time period; and

when said signal level of said wireless signal from said other apparatus is monitored by said one apparatus in said particular operation mode, a response speed at which to detect a level change in said wireless signal is reduced.

2. The short-range wireless communication system according to claim 1, wherein at least one of said portable terminal apparatus and said wireless communication apparatus has an alarm generation unit which, if said signal level drops so low that the connection state cannot be maintained, then alerts a user to the signal level drop.

3. A portable terminal apparatus having predetermined functions, comprising:

a short-range wireless communication unit for wirelessly communicating with a wireless communication apparatus at close range;

a received signal processing unit for monitoring a signal level of a wireless signal generated by said wireless communication apparatus;

an outgoing signal output unit for causing said short-range wireless communication unit to output a request asking said wireless communication apparatus to increase transmission power when said signal level of said wireless signal drops below a predetermined threshold;

a reduced power mode control unit for moving into a particular operation mode when the short-range wireless communications do not take place at least for a predetermined time period;

a function limiting unit for limiting use of said predetermined functions when said signal level of said wireless signal from said wireless communication apparatus drops so low that a state of connection with said wireless communication apparatus cannot be maintained; and

a response speed control unit for reducing a response speed at which to detect a level change in said wireless signal output from said wireless communication apparatus when said particular operation mode is in effect,

wherein said outgoing signal output unit determines whether or not to make the request for the increase in said transmission power based on the detected output having triggered the reduction of said response speed.

4. The portable terminal apparatus according to claim 3, further comprising an alarm generation unit which, if said signal level drops so low that the connection state cannot be maintained, then alerts a user to the signal level drop.

5. The portable terminal apparatus according to claim 3, wherein, when monitoring said signal level for control over said transmission power, said response speed control unit uses a signal corresponding to a mean value of signal levels detected in a predetermined number of the most recently received wireless signals.

6. The portable terminal apparatus according to claim 3, wherein, when monitoring said signal level for control over said transmission power, said response speed control unit uses the signal level of a signal acquired by delaying said wireless signal.

7. The portable terminal apparatus according to claim 3, further comprising a threshold changing unit for changing said predetermined threshold with which to compare said signal level in order to output said request asking for the increase in said transmission power.

8. A portable terminal apparatus having predetermined functions, comprising:

short-range wireless communicating means for conducting short-range wireless communications with a wireless communication apparatus;

monitoring means for monitoring a signal level of a wireless signal generated by said wireless communication apparatus;

requesting means for causing said short-range wireless communicating means to output a request asking said wireless communication apparatus to increase transmission power when said signal level of said wireless signal drops below a predetermined threshold;

operation mode controlling means for moving into a particular operation mode when said short-range wireless communications do not take place at least for a predetermined time period;

function limiting means for limiting use of said predetermined functions when said signal level of said wireless signal from said wireless communication apparatus drops so low that a state of connection with said wireless communication apparatus cannot be maintained; and

response speed controlling means for reducing a response speed at which to detect a level change in said wireless signal output from said wireless communication apparatus when said particular operation mode is in effect,

wherein said requesting means determines whether or not to make the request for the increase in said transmission power based on the detected output having triggered the reduction of said response speed.

9. A portable terminal apparatus comprising:

communicating means for conducting voice and data communications with a base station;

short-range wireless communicating means for conducting short-range wireless communications with a wireless communication apparatus using a technology called Bluetooth, a registered trademark;

monitoring means for monitoring a signal level of a wireless signal generated by said wireless communication apparatus;

requesting means for causing said short-range wireless communicating means to output a request asking said wireless communication apparatus to increase transmission power when said signal level of said wireless signal drops below a predetermined threshold;

operation mode controlling means for moving into a reduced power mode when said short-range wireless communications do not take place at least for a predetermined time period;

function limiting means for limiting use of at least part of said voice and data communications when said signal level of said wireless signal from said wireless communication apparatus drops so low that a state of connection with said wireless communication apparatus cannot be maintained; and

response speed controlling means for reducing a response speed at which to detect a level change in said wireless signal output from said wireless communication apparatus when said reduced power mode is in effect,

wherein said requesting means determines whether or not to make the request for the increase in said transmission power based on the detected output having triggered the reduction of said response speed.

10. A wireless communication apparatus for conducting short-range wireless communications with short-range wireless communication units located externally, said wireless communication apparatus comprising:

a short-range wireless communication unit for establishing a state of connection for conducting short-range wireless communications with a particular external short-range wireless communication unit;

an outgoing signal output unit for transmitting a wireless signal to said particular external short-range wireless communication unit;

a power adjustment unit for adjusting transmission power for sending said wireless signal to said particular external short-range wireless communication unit in accordance with a request from said particular external short-range wireless communication unit; and

an alarm generation unit which, in case of a disconnection from said particular external short-range wireless communication unit, alerts a user to said disconnection.

11. The wireless communication apparatus according to claim 10, further comprising a reduced power mode control unit for moving into a particular operation mode if said short-range wireless communications do not take place at least for a predetermined time period,

wherein said power adjustment unit, after moving into said particular operation mode, rejects the request to increase said transmission power.

12. The wireless communication apparatus according to claim 10, further comprising a reduced power mode control unit for moving into a particular operation mode if said short-range wireless communications do not take place at least for a predetermined time period,

wherein said power adjustment unit, after moving into said particular operation mode, reduces an adjustable upper limit of said transmission power.

13. A wireless communication apparatus for conducting short-range wireless communications with short-range wireless communication units located externally, said wireless communication apparatus comprising:

connecting means for establishing a state of connection for conducting short-range wireless communications with a particular external short-range wireless communication unit;

transmitting means for transmitting a wireless signal to said particular external short-range wireless communication unit;

power adjusting means for adjusting transmission power for sending said wireless signal to said particular external short-range wireless communication unit in accordance with a request from said particular external short-range wireless communication unit; and

alerting means which, in case of a disconnection from said particular external short-range wireless communication unit, alerts a user to said disconnection.