Electronic timepiece and reception control method of an electronic timepiece

Patent metadata

Field	Value
Publication number	US-9448539-B2
Application number	US-201414219693-A
Country	US
Kind code	B2
Filing date	Mar 19, 2014
Priority date	Mar 29, 2013
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

An electronic timepiece has a receiver device that receives at least a first satellite signal containing a first leap second value and a second satellite signal containing a second leap second value; a timekeeping device that keeps time according to the current leap second; an evaluation condition setting unit that sets an evaluation condition of the correctness of the first leap second value and the second leap second value based on the timing of first satellite signal and second satellite signal reception; and a leap second correction unit that corrects the current leap second based on the first leap second value or the second leap second value when the first leap second value and the second leap second value satisfy the set evaluation condition.

First claim

What is claimed is:

1. An electronic timepiece comprising:
a receiver unit that receives at least one satellite signal containing a respective leap second value during a single reception process;
a time data storage unit that stores a current leap second;
a timekeeping unit that keeps time according to the current leap second;
an evaluation condition setting unit that sets a first evaluation condition of the correctness of the satellite signals received in the single reception process if the number of satellite signals received within the reception process is not greater than a predefined number, and sets a second evaluation condition of the correctness of the satellite signals received in the single reception process if the number of satellites received within the reception process is greater than the predefined number, the first evaluation condition being different than the second evaluation condition; and
a leap second correction unit that corrects the current leap second stored in the time data storage unit based on the leap second value of any of the satellite signals received within the reception process if the first or second evaluation condition that is set by the evaluation condition setting unit is satisfied;
a candidate leap second value storage unit that stores a candidate leap second value, the candidate leap second value being a leap second value contained in a previous satellite signal received in a past reception process executed before the single reception process;
wherein the first evaluation condition includes:
the leap second value contained in a selected one of the satellite signals received within the single reception process and the candidate leap second value stored in the candidate leap second value storage unit are the same.

2. The electronic timepiece described in claim 1 , further comprising:
wherein the first evaluation condition further includes:
determining if the selected one of satellite signals received within the reception process is received from a positioning information satellite in normal satellite health condition.

3. The electronic timepiece described in claim 2 , further comprising:
a candidate leap second value updating unit;
wherein the first evaluation condition further includes:
if the respective leap second value of the selected satellite signal is determined to not be the same as the candidate leap second value stored in the candidate leap second value storage unit, then updating the candidate leap second value to the leap second value contained in the selected satellite signal.

4. The electronic timepiece described in claim 1 , wherein the second evaluation condition includes:
the leap second values from any two satellite signals received by the receiver unit during the same single reception process are equal.

5. The electronic timepiece described in claim 1 , further comprising:
wherein the first evaluation condition further includes:
if no candidate leap second value is stored in the candidate leap second value storage unit, then storing the leap second value of any of the satellite signals received by the receiver unit during the single reception process into the candidate leap second value storage unit as the candidate leap second value, and determining that the evaluation condition is not satisfied;
if the candidate leap second value is stored in the candidate leap second value storage unit, then determining if the selected one of the satellite signals received within the reception process is from a positioning information satellite in normal satellite health; and

wherein the second evaluation condition includes:
the leap second values from any two satellite signals received by the receiver unit during the same single reception process are equal.

6. The electronic timepiece described in claim 1 , wherein:
the first and second evaluation conditions include determining if the received satellite signals were received from positioning information satellites in normal satellite health.

7. The electronic timepiece described in claim 1 , wherein:
said at least one satellite signal additionally contains a future leap second value; and
at least one of said first evaluation condition and second evaluation condition includes determining if the difference between the leap second value contained in the selected one of the received satellite signals and the future leap second value contained in the selected one of the received satellite signals is within a range from −1 second to +1 second.

8. The electronic timepiece described in claim 1 , wherein:
said at least one satellite signal additionally contains a future leap second value and a scheduled leap second event; and
at least one of said first evaluation condition and second evaluation condition includes determining if the scheduled leap second event of the selected one of the received satellite signals is after the date that the selected satellite signal was received if the respective leap second value and future leap second value of the selected one of the received satellite signals are different values.

9. The electronic timepiece of claim 1 , wherein the reception process is from when reception of leap second value information starts until the reception process ends or until reception times out.

10. The electronic timepiece of claim 1 , wherein said predefined number is one.

11. The electronic timepiece of claim 1 , wherein:
the reception process is from when reception of leap second value information starts until the reception process ends or until reception times out; and
said predefined number is one.

12. The electronic timepiece described in claim 11 , wherein the second evaluation condition includes:
determining if the leap second values from any two satellite signals received by the receiver unit during the same single reception process are equal.

13. The electronic timepiece described in claim 12 , wherein the first evaluation condition further includes:
if no candidate leap second value is stored in the candidate leap second value storage unit, then storing the leap second value of the one received satellite signal into the candidate leap second value storage unit as the candidate leap second value, and determining that the evaluation condition is not satisfied.

14. An electronic timepiece comprising:
a time data storage unit that stores a current leap second;
a timekeeping unit that keeps time according to the current leap second;
a receiver unit that receives a first satellite signal in a first time reception process to receive first current time information, and receives a second satellite signal after the first satellite signal in a second time reception process to receive second current time information that is different from the first current time information, the second time reception process being executed after the first time reception process ends;
a candidate leap second value storage unit that stores a first leap second value contained in the first satellite signal as a candidate leap second value; and
a leap second correction unit that corrects the current leap second stored in the time data storage unit based on at least one of a second leap second value contained in the second satellite signal and the candidate leap second value when the second leap second value is the same as the candidate leap second value.

15. A reception control method of an electronic timepiece having a receiver unit that receives satellite signals, and a timekeeping unit that keeps time according to the current leap second, the control method comprising:
providing a time data s

Assignees

• Seiko Epson Corp

Inventors

• Akiyama Toshikazu

Classifications

• G04R20/06 Primary

  Decoding time data; Circuits therefor · CPC title

• G04R20/00

  Setting the time according to the time information carried or implied by the radio signal · CPC title

• G04R20/02 Primary

  the radio signal being sent by a satellite, e.g. GPS · CPC title

• G04R20/04

  Tuning or receiving; Circuits therefor · CPC title