UrsaNav Follows Up with Second Wide-Area Timing Tests

This week, UrsaNav once again transmitted from the former USCG Loran Support Unit (LSU) facility in Wildwood, New Jersey. To ensure that those interested understand that the USCG has no intent to acquire, operate, or provide a wireless time technology or services, UrsaNav has renamed the LSU — it’s new facility name is the Diamond Beach Facility, or “dBF.”

In a statement released today, UrsaNav said:

“Our main purpose for on-air testing at this time is to demonstrate wide-area precise time distribution using terrestrial, ground-wave RF solutions. However, a robust timing solution uses on-signal data channel(s) for nanosecond-level corrections, so we are also testing a variety of modulation techniques that provide significant throughput gains over the current 100-180 BPS methods.

“Our current equipment suites consist of the Nautel NL Series prototype transmitters, Symmetricom Timing and Frequency Equipment (TFE), and UrsaNav UN-150 eLoran Timing Receivers.

“We are not simply transmitting eLoran. We are also evaluating some improvements to eLoran that do not change the underlying signal structure. Finally, we are testing various alternative LF solutions that include new waveforms and modulation techniques.

“We have established preliminary monitor sites at five locations: Boston, Massachusetts; Chambersburg, Pennsylvania; Leesburg and Chesapeake, Virginia; and Charleston, South Carolina. We are scouting for additional monitor sites at distances of up to 1,500 miles from our current transmitting location.

“During this week’s testing, we tightened the synchronization of our transmissions to within 10 ns of UTC. We tested continuously for periods in excess of 24 hours. Without the use of any propagation corrections or differential monitoring, we successfully demonstrated UTC traceability to within +/- 30 ns at 160 miles and to within +/- 70 ns at 500 miles. Several acquisition trials showed that our receivers can very quickly acquire the LF signal and steer to within 50 ns of UTC. At all distances, our receivers met the ITU and ETSI Maximum Time Interval Error (MTIE) masks for Primary Reference Clocks.

“Additional on-air tests are planned for next week, so stay tuned for the third part of our continuing series on wide-area timing.”