Wireless clock system

• US 20050259722A1
• Filed: 05/21/2004
• Published: 11/24/2005
• Est. Priority Date: 05/21/2004
• Status: Abandoned Application

• Current Assignee: American Time & Signal Company
• Original Assignee: American Time & Signal Company
• Inventors: Vanlonden, Reginald, Kopp, Bernhard
• Application Number:
  US10/850,829
• Publication Number:
  US 20050259722A1
• Time in Patent Office: Days
• US Class Current: 375/145
• CPC Class Codes: H04B 15/04 the interference being caused by substantially sinusoidal oscillations, e.g. in a receiver or in a tape-recorder
• CPC Class Codes: H04B 2201/70715 with application-specific features
• CPC Class Codes: H04B 2215/064 Reduction of clock or synthesizer reference frequency harmonics
• CPC Class Codes: H04B 2215/067 by modulation dispersion

Abstract

A wireless clock system is disclosed. The system includes a primary clock device and at least one secondary clock device, where the secondary clock device is an analog clock, a digital clock, or a signal device. The primary clock device is adapted to wirelessly receive a reference time signal and wirelessly broadcast a master time signal based upon the reference signal to the secondary clock device. The secondary clock device wirelessly receives the signal and updates its displayed time accordingly. The secondary clock device can include a controller adapted to translate the wirelessly received signal into an alternate format recognized by a secondary clock device movement to synchronize the secondary clock device movement to the nearest second. The secondary clock device can further include an adapter module for compatibility with a wired clock system

Claims

1. A wireless clock system comprising:

a primary clock device comprising receiver circuitry adapted to receive a long-range wireless reference time signal, a primary controller in electrical communication with the receiver circuitry and adapted to maintain a system time based upon the reference time signal, and transmitter circuitry in electrical communication with the primary controller and adapted to wirelessly broadcast the system time as a short-range spread spectrum signal; and

at least one secondary clock device comprising an adapter in electrical communication with a clock movement adapted to receive a synchronized time code, the adapter including receiver circuitry adapted to receive the system time spread spectrum signal and a microcontroller;

wherein the microcontroller is operable to encode a received short-range spread spectrum signal as a synchronized time code and transmit the synchronized time code to the clock movement, and wherein the clock movement is adapted to achieve system time synchronization after receiving the synchronized time code.

2. The system of claim 1, wherein the long-range wireless reference time signal comprises a global positioning system-based (GPS) signal.

3. The system of claim 1, wherein the short-range spread spectrum signal is broadcast in a band of about 902 megahertz to about 928 megahertz.

4. The system of claim 1, wherein the primary clock device further comprises a liquid crystal display (LCD) for displaying the system time.

5. The system of claim 4, wherein the primary clock device further comprises an external keypad for programming the primary clock device.

6. The system of claim 1, wherein the primary clock device further comprises an external computer interface for connection to a computer.

7. The system of claim 1, wherein the synchronized time code is a WWVB radio signal format.

8. The system of claim 1, wherein the at least one secondary clock device comprises an analog clock that includes an enclosure adapted for wall mounting, and wherein the clock movement comprises an analog clock movement including hour, minute, and second indicators.

9. The system of claim 1 further comprising a repeater device, the repeater device adapted to receive the short-range spread spectrum signal from the primary clock device and re-broadcast the received short-range spread spectrum signal to at least one secondary clock device.

10. The system of claim 1, wherein the at least one secondary clock device further comprises transmitter circuitry adapted to wirelessly transmit secondary clock device status information to the primary clock device.

11. A wireless clock system comprising:

a primary clock device adapted to receive a reference time signal, a primary controller adapted to maintain a system time based upon the reference time signal, and transmitter circuitry in electrical communication with the primary controller and adapted to wirelessly broadcast the system time as a short-range spread spectrum signal; and

at least one secondary clock device comprising an adapter in electrical communication with a clock movement adapted to receive a synchronized time code, the adapter including a microcontroller and receiver circuitry adapted to receive the short-range spread spectrum signal;

wherein the microcontroller is operable to encode a received short-range spread spectrum signal in a synchronized time code and transmit the synchronized time code to the clock movement, and wherein the clock movement is adapted to achieve system time synchronization after receiving the synchronized time code.

12. The system of claim 11, wherein the primary clock device further comprises an external computer interface for connection to a computer network, and wherein the reference time signal is received from the computer network.

13. The system of claim 12, wherein the computer network comprises the Internet.

14. The system of claim 13, wherein the synchronized time code is a WWVB radio signal format.

15. The system of claim 13, wherein the at least one secondary clock device further comprises transmitter circuitry adapted to wirelessly transmit secondary clock device status information to the primary clock device.

16. A method of synchronizing a plurality of time-keeping devices, the method comprising the steps of:

receiving, at a primary clock device, a long-range wireless reference time signal;

updating a master time maintained by the primary clock device based upon the reference time signal;

wirelessly broadcasting the master time from the primary clock device to the plurality of time-keeping devices as a short-range signal;

receiving, at a controller of a time-keeping device, the broadcast master time;

converting the broadcast master time to a synchronized time code;

transmitting the synchronized time code from the controller to a clock movement of the time-keeping device; and

updating the time-keeping device based upon the synchronized time code, thereby synchronizing the plurality of time-keeping devices with the master time and reference time signal.

17. The method of claim 16, wherein the long-range wireless reference time signal is a global positioning system-based (GPS) signal.

18. The method of claim 16, wherein the master time is wirelessly broadcast in a short-range spread spectrum signal.

19. The method of claim 18, wherein the short-range spread spectrum signal is broadcast in a band of about 902 megahertz to about 928 megahertz.

20. The method of claim 17, wherein the synchronized time code is a WWVB radio signal format.

21. The method of claim 17, wherein the time-keeping device is an analog clock adapted for wall-mounting and the clock movement is an analog clock movement including hour, minute, and second indicators.

22. The method of claim 17, further comprising the step of wirelessly transmitting information from the time-keeping device to the primary clock device.

23. A synchronized clock system comprising:

a primary clock device comprising receiver circuitry adapted to receive a long-range wireless reference time signal, a primary controller in electrical communication with the receiver circuitry and adapted to maintain a system time based upon the reference time signal, and transmitter circuitry in electrical communication with the primary controller and adapted to broadcast a system time signal; and

at least one secondary clock device comprising a secondary controller in electrical communication with a clock movement adapted to receive a synchronized time code, the secondary controller including an adapter module comprising receiver circuitry to receive the system time signal;

wherein the secondary controller is operable to encode a received system time signal as a synchronized time code and transmit the synchronized time code to the clock movement, and wherein the clock movement is adapted to achieve system time synchronization after receiving the synchronized time code.

24. The clock system of claim 23, wherein the system time signal is broadcast by the transmitter circuitry as a short-range wireless spread spectrum signal.

25. The clock system of claim 24, wherein the short-range wireless spread spectrum signal is broadcast in a band of about 902 megahertz to about 928 megahertz.

26. The clock system of claim 24, wherein the system time signal is broadcast by the transmitter circuitry on a wired network, and wherein the adapter module is configured to operably connect to the wired network.

27. The system of claim 24, wherein the long-range wireless reference time signal comprises a global positioning system-based (GPS) signal.

28. The system of claim 24, wherein the primary clock device further comprises a liquid crystal display (LCD) for displaying the system time.

29. The system of claim 28, wherein the primary clock device further comprises an external keypad for programming the primary clock device.

30. The system of claim 24, wherein the primary clock device further comprises an external computer interface for connection to a computer.

31. The system of claim 24, wherein the synchronized time code is a WWVB radio signal format.

32. The system of claim 24, wherein the at least one secondary clock device comprises an analog clock having a case configured for wall-mounting, and wherein the movement comprises an analog clock movement having hour, minute, and second indicators.

33. The system of claim 24, wherein the at least one secondary clock device comprises a plurality of secondary clock devices, and wherein at least one of the plurality of secondary clock devices omits the secondary controller and is configured to receive the system time signal and directly achieve system time synchronization from the system time signal.

34. The system of claim 33, wherein the long-range wireless reference time signal comprises a global positioning system-based (GPS) signal, and wherein the system time signal is broadcast by the transmitter circuitry as a short-range wireless spread spectrum signal.

35. A primary clock device comprising:

a receiver including an antenna and adapted to wirelessly receive a long-range reference time signal;

a microcontroller in electrical communication with the receiver and including an internal time-keeping device to maintain a master time based upon the long-range reference time signal; and

spread spectrum transmitter in electrical communication with the microcontroller and operable to receive the master time from the microcontroller and wirelessly transmit the master time as a short-range spread spectrum signal.

36. The primary clock device of claim 35, wherein the long-range reference time signal comprises a global positioning system (GPS) signal.

37. The primary clock device of claim 35, wherein the short-range spread spectrum signal is broadcast in the band of about 902 megahertz to about 928 megahertz.

38. The primary clock device of claim 35 further comprising a liquid crystal display (LCD) for displaying the master time.

39. The primary clock device of claim 38 further comprising an external keypad in electrical communication with the microcontroller for programming the primary clock device.

40. A secondary clock device comprising:

a spread spectrum receiver adapted to receive a wireless short-range spread spectrum time synchronization signal;

a controller in electrical communication with the receiver to receive the time synchronization signal and determine a time correction; and

an analog clock movement, the analog clock movement comprising an hour, a minute, and a second indicator disposed on a clock display enclosed in a housing, wherein the analog clock movement is adapted to receive a time correction signal from the controller and is operable to update the hour, minute, and second indicators in accordance with the time correction signal.

41. The secondary clock device of claim 40, wherein the housing is adapted for wall hanging.

42. The secondary clock device of claim 40, wherein the short-range spread spectrum signal is in the band of about 902 megahertz to about 928 megahertz.

43. The secondary clock device of claim 40, wherein the analog clock movement is configured to receive a WWVB radio signal format time correction signal, and wherein the controller further comprises a microprocessor operable to translate the time correction into a WWVB radio signal format time correction signal and transmit the WWVB radio signal format time correction signal to the analog clock movement.

44. A secondary clock device comprising:

an adapter module including a first receiver in electrical communication with a microcontroller, wherein the first receiver is adapted to receive a time synchronization signal; and

an analog clock movement, the analog clock movement comprising an hour, a minute, and a second indicator disposed on a clock display enclosed in a housing, wherein the analog clock movement is in electrical communication with the adapter module to receive a time correction signal calculated by the microcontroller based upon the time synchronization signal, and wherein the analog clock movement is operable to update the hour, minute, and second indicators in accordance with the time correction signal.

45. The secondary clock device of claim 44, wherein the first receiver comprises a spread spectrum receiver adapted to receive a wireless short-range spread spectrum time synchronization signal.

46. The secondary clock device of claim 45, wherein the short-range spread spectrum signal is in the band of about 902 megahertz to about 928 megahertz.

47. The secondary clock device of claim 45 further comprising a second receiver comprising a long-range signal receiver, wherein the secondary clock device is adapted to switch between the first receiver and the second receiver based upon time synchronization signal availability.

48. The secondary clock device of claim 47, wherein the housing is adapted for wall-mounting.

49. The secondary clock device of claim 44, wherein the first receiver comprises a long-range signal receiver.

50. The secondary clock device of claim 49, wherein the time synchronization signal comprises a global positioning system (GPS) signal.

51. A clock adapter module comprising:

a receiver adapted to receive a short-range spread spectrum reference time signal;

a microcontroller in electrical communication with the receiver; and

an analog clock movement interface adapted to couple the clock adapter module a secondary analog clock movement;

wherein the microcontroller is configured to receive the short-range spread spectrum reference time signal from the receiver, convert the short-range spread spectrum reference time signal to a long-range reference time signal format signal, and transmit the long-range reference time signal format signal to the secondary analog clock movement via the analog clock movement interface to synchronize the analog clock movement to a nearest second.

52. A method of creating a primary-secondary clock system comprising the steps of:

providing a primary clock, wherein the primary clock comprises

a primary receiver including an antenna and adapted to receive a wireless long-range reference time signal,

a primary microcontroller in electrical communication with the primary receiver and including an internal time-keeping device to maintain a master time based upon the long-range reference time signal, and

spread spectrum transmitter in electrical communication with the primary microcontroller and operable to receive the master time from the primary microcontroller and wirelessly transmit the master time as a short-range spread spectrum signal;

providing a plurality of secondary clocks, wherein each of the plurality of the secondary clocks comprises

a first receiver adapted to receive a wireless long-range reference time signal and in electrical communication with a secondary microcontroller,

an adapter module including a second receiver in electrical communication with the secondary microcontroller, wherein the second receiver is adapted to receive a short-range spread spectrum signal, and

an analog clock movement, the analog clock movement comprising an hour, a minute, and a second indicator disposed on a clock display enclosed in a housing, wherein the analog clock movement is in electrical communication with the secondary microcontroller to receive a time correction signal calculated by the secondary microcontroller;

determining, at the secondary microcontroller, whether the first receiver received a wireless long-range reference time signal;

if a long-range reference time signal was received, calculating the time correction signal based upon the long-range reference time signal and transmitting the time correction signal to the analog clock movement to synchronize the analog clock movement with the long-range reference time signal; and

if a long-range reference time signal was not received, using the adapter module to receive a short-range spread spectrum signal from the primary clock, calculating the time correction signal based upon the short-range spread spectrum signal, and transmitting the time correction signal to the analog clock movement to synchronize the analog clock movement with the short-range spread spectrum signal.

53. The method of claim 52, wherein the long-range reference time signal comprises a global positioning system (GPS) signal, and wherein the short-range spread spectrum signal is in the band of about 902 megahertz to about 928 megahertz.

54. The method of claim 52, wherein the housing is adapted for wall-mounting.