Radio range verification method, wireless telecommunications equipment implementing this method, base station and mobile handset of such equipment

• US 6,330,437 B1
• Filed: 03/24/1999
• Issued: 12/11/2001
• Est. Priority Date: 03/31/1998
• Status: Expired due to Fees

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Bozzetto, Olivier, Bordeau, Jean-Pascal
• Primary Examiner(s): Legree, Tracy
• Assistant Examiner(s): GELIN, JEAN ALLAND
• Application Number:
  US09/275,631
• Time in Patent Office: 993 Days
• Field of Search: 455/405, 455/420, 455/421, 455/423, 455/67.7, 455/513, 455/456, 455/461, 455/462, 455/465, 455/406, 455/411, 455/422, 370/315, 370/401
• US Class Current: 455/421
• CPC Class Codes: H04M 1/72505 Radio link set-up procedures
• CPC Class Codes: H04W 16/24 Cell structures
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

A method of verifying effective radio range increases the distance over which wireless mobiles can be used around the base station. The level of the radio field received by the base station is measured to detect a range-limit electric signal. Instead of cutting off the communication at the detection of this signal, a presence verification protocol is initiated that includes exchanging presence confirmation after messages between the base station and the handset, and cutting off the communication only when one of the parts no longer receives a confirmation message after a predefined time period.

Claims

1. A range-limit verification method in a wireless telecommunications system comprising at least two parts communicating by radio channel inside a coverage area, the method comprising:

a. reading an electric field level received by the second part and transmitted by the first part

b. generating a range-limit signal when an electric field level received by the second part falls below a predetermined detection threshold;

c. triggering a presence verification step in response to said range-limit signal for verifying presence of said first part inside the coverage area, said presence verification comprising;

i. enabling said second part to transmit a request message requesting confirmation of presence of said first part; and

ii. enabling said first part to respond to said request message by transmitting a presence-confirmation signal for receipt by said second part for verifying said presence,

wherein said communicating by radio channel is uninterrupted when said parts are maintained in an off-hook condition while one of said parts is moved from a range-limit detection are to a periphery of said coverage area thereby increasing a range of use.

2. A method as claimed in claim 1, said presence verification step comprises:

repeating said presence verification step as long as said presence-confirmation signal is received by said second part in a defined time period; and

,

terminating said communicating between said first part and said second part when said presence-confirmation signal has not been detected by said second part in a defined time period.

3. A method as claimed in claim 2, wherein said repeating step is stopped when, during said reading step, a received electric field level is detected that exceeds a predetermined detection threshold.

4. Telecommunications equipment comprising:

at least a first and a second part which may communicate by radio channel inside a coverage area,

means for detecting an electric field level received by the second part and transmitted by the first part for detecting a range-limit signal,

presence verification means for verifying the presence of the first part inside said area,

said presence verification means being triggered as a result of the detection of said range-limit signal and including transmitting means for transmitting a radio message requesting a confirmation of presence to said first part.

5. Telecommunications equipment as claimed in claim 4, wherein said transmitting means sends said message requesting said confirmation of presence to said first part at given time intervals, and

wherein the presence verification means further include:

delay means for triggering a delay that corresponds to said time intervals,

receiving means for receiving said presence confirmation message,

means for cutting off radio communications, triggered if said presence confirmation message is not received by said second part in a given period of time.

6. Telecommunications equipment as claimed in claim 4, characterized in that it is in conformity with an analog standard of the type CTO.

7. A base station formed by said second part of wireless telephony equipment as claimed in claim 4, said first part being formed by a mobile handset, characterized in that it comprises

said means for detecting a received electric field level for measuring the electric field level emitted by the handset,

said presence verification means for verifying the presence of the handset inside said radio coverage area.

8. A mobile handset formed by said second part of wireless telephony equipment as claimed in claim 4, said first part being formed by a base station, characterized in that it comprises:

said means for detecting a received electric field level for measuring the electric field level emitted by the base station,

said presence verification means for verifying the presence of the base station inside said radio coverage area.

9. Telecommunications equipment as claimed in claim 4, wherein said presence verification means are deactivated when a received electric field level is detected that exceeds a predetermined threshold.

10. A wireless telecommunication network comprising:

a first unit; and

a second unit in communication with said first unit wirelessly;

said first unit transmitting a first signal to said second unit;

said first and second units repeating a presence confirmation protocol comprising;

said second unit transmitting a request message requesting confirmation of presence of said first unit in response to detection of said first signal if said first signal is below a predetermined detection threshold;

said first unit transmitting a presence-confirmation signal in response to said request message;

said first and second units terminating said communication between them when said presence-confirmation signal has not been detected by said second unit in a defined time period; and

,

stopping said repeating if said first signal exceeds said predetermined detection threshold.