Time distribution with multi-band antenna

• US 9,760,062 B2
• Filed: 10/17/2013
• Issued: 09/12/2017
• Est. Priority Date: 10/19/2012
• Status: Active Grant

• Current Assignee: Schweitzer Engineering Laboratories, Incorporated
• Original Assignee: Schweitzer Engineering Laboratories, Incorporated
• Inventors: Achanta, Shankar V., Whitehead, David E., Loehner, Henry
• Primary Examiner(s): Lau, Tung
• Application Number:
  US14/056,170
• Publication Number:
  US 20140114608A1
• Time in Patent Office: 1,426 Days
• Field of Search: 702176
• CPC Class Codes: G01S 19/23 Testing, monitoring, correcting or calibrating of receiver elements
• CPC Class Codes: G04F 10/10 by measuring electric or magnetic quantities changing in proportion to time

Abstract

Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period.

Claims

1. A system comprising:

a multi-band antenna configured to receive a first time signal from a first time source, and a second time signal from a second time source independent from the first time source;

a time signal distribution device comprising;

a first receiver in communication with the multi-band antenna, configured to receive the first time signal;

a second receiver in communication with the multi-band antenna, configured to receive the second time signal, wherein the second time signal is less accurate than the first time signal;

an output configured to provide an output time signal to a time dependent device; and

a time quality module configured to compare the first time signal with the second time signal and detect an error condition of the first time signal in response to a variation of the first time signal from the second time signal exceeding a defined threshold.

2. The system of claim 1, wherein the first time source is a global navigation satellite system (GNSS).

3. The system of claim 1, wherein the second time signal is a WWVB signal.

4. The system of claim 1 further comprising, an indicator configured to notify a user when an error condition is detected.

5. The system of claim 1, wherein the output is configured to provide the first time signal to the time dependent device.

6. The system of claim 1, wherein, in response to detecting an error condition, the output is configured to provide the second time signal to the time dependent device.