Electronic timepiece capable of receiving signals from satellites

• US 5,408,444 A
• Filed: 06/16/1992
• Issued: 04/18/1995
• Est. Priority Date: 06/19/1991
• Status: Expired due to Term

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Kinoshita, Satoshi, Kita, Kazunori
• Primary Examiner(s): Miska, Vit W.
• Application Number:
  US07/899,254
• Time in Patent Office: 1,036 Days
• Field of Search: 368/10, 368/46, 368/47, 343/225, 455/12, 455/51
• US Class Current: 368/47
• CPC Class Codes: G04G 9/0076 in which the time in another time-zone or in another city can be displayed at will
• CPC Class Codes: G04R 20/06 Decoding time data; Circuits therefor

Abstract

In an electronic timepiece having a signal receiving function, the present time at a place where a user is located can be displayed without designating a regional name. The quasi-distance data between the satellites and the signal receiving point is calculated based upon the delay times of the signals transmitted from the satellites. The positional information about the signal receiving point is obtained from four quasi-distance data. Subsequently, this positional information is compared with the longitude/latitude data previously stored in ROM, to search a city located nearest this signal receiving point. Furthermore, a judgement is made whether or not the city located nearest the present receiving point is coincident with the city located nearest the preceding receiving point. If these cities are coincident with each other, then the present time of the city stored in the time counting register is directly displayed. If no coincidence is established, then the time counted by the time counting unit is corrected based upon the time difference data about the city located nearest the present signal receiving point, and also the corrected time is displayed in combination with the name of this city.

Claims

1. An electronic timepiece having a signal receiving function, comprising:

time counting means for counting time information;

regional information storing means for storing regional information about a region having the time information counted by the time counting means as present time;

signal receiving means for receiving signals transmitted from a plurality of satellites;

receiving-position calculating means for calculating regional information about a signal receiving point based on the signals received by the signal receiving means;

judging means for judging whether the regional information calculated by the receiving-position calculating means is different from the regional information stored in the regional information storing means; and

time controlling means for obtaining time information of the signal receiving point from the regional information calculated by the receiving-position calculating means, the regional information stored in the regional information storing means and the time information counted by the time counting means, when the judging means determines that the regional information calculated by the receiving-position calculating means and the regional information stored in the regional information storing means are different from each other.

2. An electronic timepiece having a signal receiving function as claimed in claim 1, wherein said signal reception by the signal receiving means is performed every time the time information counted by the time counting means has passed a predetermined time period.

3. An electronic timepiece having a signal receiving function as claimed in claim 1, further comprising:

display means for displaying the time information about the signal receiving point obtained by said time controlling means.

4. An electronic timepiece having a signal receiving function as claimed in claim 1, wherein said time controlling means includes:

changing means for changing the time information counted by the time counting means into the time information about the signal receiving point.

5. An electronic timepiece having a signal receiving function as claimed in claim 1, wherein said time controlling means includes:

position/time difference storage means for storing time difference information among regional information about regional points in the world and the world standard time in a relevant relationship, the time difference information being read out from the position/time difference storage means based upon the regional information calculated by said receiving-position calculating means so as to obtain time information about said signal receiving point.

6. An electronic timepiece having a signal receiving function as claimed in claim 5, wherein the regional information stored in said position/time difference storage means corresponds to longitude/latitude data.

7. An electronic timepiece having a signal receiving function as claimed in claim 1, further comprising:

receiving-position information display means for displaying the regional information about the signal receiving point, which has been calculated by said receiving-position calculating means.

8. An electronic timepiece having a signal receiving function as claimed in claim 1, wherein said plurality of satellites are satellites used in the Global Positioning System.

9. An electronic timepiece having a signal receiving function as claimed in claim 1, wherein:

the time counting operation by said time counting means is performed in response to a first clock signal derived from a first oscillating means; and

the signal reception by said signal receiving means is executed in response to a clock signal having a frequency higher than that of said first clock signal.

10. An electronic timepiece having a signal receiving function as claimed in claim 1, further comprising:

a first microprocessor means for controlling the time counting operation by said time counting means; and

second microprocessor means for controlling the signal reception by said signal receiving means.

12. An electronic timepiece having a signal receiving function as claimed in claim 1, wherein said signal reception by the signal receiving means is performed every time the time information counted by the time counting means has passed a predetermined time period.

13. An electronic timepiece having a signal receiving function as claimed in claim 1, further comprising:

display means for displaying the time information about the signal receiving point obtained by said time controlling means.

14. An electronic timepiece having a signal receiving function as claimed in claim 1, further comprising:

moon data display means for optically displaying data related to the moon obtained by said moon data calculating means.

15. An electronic timepiece having a signal receiving function as claimed in claim 14, wherein said data related to the moon corresponds to at least one of moon-age data and moon phase data.

11. An electronic timepiece having a signal receiving function, comprising:

time counting means for counting time information;

regional information storing means for storing regional information about a region having the time information counted by the time counting means as present time;

signal receiving means for receiving signals transmitted from a plurality of satellites;

receiving-position calculating means for calculating regional information about a signal receiving point based on the signals received by the signal receiving means;

judging means for judging whether the regional information calculated by the receiving-position calculating means is different from the regional information stored in the regional information storing means;

time controlling means for obtaining time information of the signal receiving point from the regional information calculated by the receiving-position calculating means, the regional information stored in the regional information storing means and the time information counted by the time counting means, when the judging means determines that the regional information calculated by the receiving-position calculating means and the regional information stored in the regional information Storing means are different from each other; and

moon data calculating means for obtaining data related to the moon based upon the time information of the signal receiving point calculated by said time controlling means.

16. An electronic timepiece having a signal receiving function as claimed in claim 11, further comprising:

receiving-position information display means for displaying the regional information about the signal receiving point, which has been calculated by said receiving-position calculating means.

17. An electronic timepiece having a signal receiving function as claimed in claim 11, wherein said plurality of satellites are satellites used in the Global Positioning System.

18. An electronic timepiece having a signal receiving function as claimed in claim 11, wherein:

the time counting operation by said time counting means is performed in response to a first clock signal derived from a first oscillating means; and

the signal reception by said signal receiving means is executed in response to a clock signal having a frequency higher than that of said first clock signal.

19. An electronic timepiece having a signal receiving function, comprising:

time counting means for counting both of date information and time information;

regional information storing means for storing regional information about a region having the date information and the time information as present time, both counted by the time counting means;

signal receiving means for receiving signals transmitted from a plurality of satellites;

receiving-position calculating means for calculating regional information about a signal receiving point based on the signals received by the signal receiving means;

judging means for judging whether the regional information calculated by the receiving-position calculating means is different from the regional information stored in the regional information storing means;

time controlling means for obtaining both of the date information and the time information of the signal receiving point from the regional information calculated by the receiving-position calculating means, the regional information stored in the regional information storing means, and the date information and the time information counted by the time counting means, when the judging means determines that the regional information calculated by the receiving-position calculating means and the regional information stored in the regional information storing means are different from each other;

sunrise/sunset time data calculating means for calculating time information about the sunrise and sunset based upon the date information at the signal receiving point calculated by said time controlling means; and

sunrise/sunset time display means for displaying the time information about the sunrise and sunset calculated by said sunrise/sunset time data calculating means.

20. An electronic timepiece having a signal receiving function as claimed in claim 19, wherein said signal reception by the signal receiving means is performed every time the time information counted by the time counting means has passed a predetermined time period.

21. An electronic timepiece having a signal receiving function as claimed in claim 19, further comprising:

display means for displaying the date and time information about the signal receiving point obtained by said time controlling means.

22. An electronic timepiece having a signal receiving function as claimed in claim 19, further comprising:

receiving-position information display means for displaying the regional information about the signal receiving point, which has been calculated by said receiving-position calculating means.

23. An electronic timepiece having a signal receiving function as claimed in claim 19, wherein said plurality of satellites are satellites used in the Global Positioning System.

24. An electronic timepiece having a signal receiving function as claimed in claim 19, wherein:

the time counting operation by said time counting means is performed in response to a first clock signal derived from a first oscillating means; and

the signal reception by said signal receiving means is executed in response to a clock signal having a frequency higher than that of said first clock signal.