Position measurement apparatus that detects location by receiving external signals

• US 6,426,719 B1
• Filed: 04/05/2000
• Issued: 07/30/2002
• Est. Priority Date: 04/07/1999
• Status: Expired due to Term

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Kitta, Noriyuki, Nagareda, Hirofumi
• Primary Examiner(s): Zanelli, Michael J.
• Assistant Examiner(s): Gibson, Eric M
• Application Number:
  US09/543,719
• Time in Patent Office: 846 Days
• Field of Search: 342/357.13, 342/357.12, 342/357.17, 342/357.07, 342/357.06, 340/573.1, 340/573.7
• US Class Current: 342/357.52
• CPC Class Codes: G01C 21/20 Instruments for performing navigational calculations G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01S 19/34 Power consumption

Abstract

A position measurement apparatus comprises at receiving unit, control unit, and detection unit that detect the motion of device, the position of device, or wearing situation of device, and the timing of receiving information by the receiving unit is controlled by the control unit in accordance with the detection results by the detection unit.

Claims

1. A portable position measurement apparatus that can be worn by a user, said apparatus comprising:

a position measurement unit that receives position measurement information transmitted from satellites, and that measures a present location based on the received information;

a detection unit that detects whether or not the user is wearing the apparatus; and

a control unit that ends measurement of the present location by said position measurement unit when said detection unit detects that the user is not wearing the apparatus.

2. The position measurement apparatus of claim 1, wherein said detection unit comprises a temperature detector that detects a temperature of a specified part of the apparatus, and said detection unit detects whether or not the user is wearing the apparatus based on a temperature change in a specified period of time.

3. The position measurement apparatus of claim 1, wherein said detection unit comprises a tilt angle detector that detects a posture of the apparatus, and said detection unit detects whether or not the user is wearing the apparatus based on whether or not the posture of the apparatus remains constant for a specified period of time.

4. A portable position measurement apparatus that can be worn by a user, said apparatus comprising:

a position measurement unit that receives position measurement information transmitted from satellites, and that measures a present location based on the received information;

a detection unit that detects whether or not the user is wearing the apparatus; and

a control unit that starts measurement of the present location by said position measurement unit when said detection unit detects that the user is wearing the apparatus.

5. The position measurement apparatus of claim 4, wherein said detection unit comprises a temperature detector that detects a temperature of a specified part of the apparatus, and said detection unit detects whether or not the user is wearing the apparatus based on a temperature change in a specified period of time.

6. The position measurement apparatus of claim 4, wherein said detection unit comprises a tilt angle detector that detects a posture of the apparatus, and said detection unit detects whether or not the user is wearing the apparatus based on whether or not the posture of the apparatus remains constant for a specified period of time.

7. The position measurement apparatus of claim 4, wherein said detection unit comprises a vibration detector that detects vibration of the device, and said detection unit detects whether or not the user is wearing the apparatus based on whether a duration of vibration is shorter than a specified period of time.