New eLoran Transmitter in Cumbria will Revolutionise Telecom Timing Availability

by Charles Curry, Managing Director of Chronos Technology

A technological phoenix has risen from the legacy of a post-war terrestrial positioning, navigation and timing (PNT) system to provide a massive boost to the augmentation and authentication of GPS timing signals. Loran-C was the traditional method of knowing your location until satellite PNT systems emerged, culminating in the all pervasive Global Positioning System (GPS) PNT system.

Figure 1: eLoran Transmitter

In a move that has signalled the re-emergence of the technology, eLoran has now received US Dept for Homeland Security backing.

Extract from US DHS Press Release Announced on Feb 7^th 2008.

“Today the U.S. Department of Homeland Security will begin implementing an independent national positioning, navigation and timing system that complements the Global Positioning System (GPS) in the event of an outage or disruption in service. 

The enhanced Loran, or eLoran, system will be a land-based, independent system and will mitigate any safety, security, or economic effects of a GPS outage or disruption. GPS is a satellite-based system widely used for positioning, navigation, and timing.  The eLoran system will be an enhanced and modernized version of Loran-C, long used by mariners and aviators and originally developed for civil marine use in coastal areas.

In addition to providing backup coverage, the signal strength and penetration capability of eLoran will provide support to first responders and other operators in environments that GPS cannot support, such as under heavy foliage, in some underground areas, and in dense high-rise structures. The system will use modernised transmitting stations and an upgraded network.”

This important announcement from the USA now effectively gives the green light for eLoran based applications to emerge. In a move of exciting technological foresight, The General Lighthouse Authorities (GLA), backed by the UK Dept for Transport has commissioned the world’s first new eLoran Transmitter site at Anthorn in Cumbria which was brought into operation in December 2007. With a frequency only half that of the well known BBC Radio 4 long wave signal, eLoran signals have phenomenal penetration capabilities.

Figure 2: eLoran Antenna

Charles Curry, Managing Director of Chronos Technology Ltd commented “This is a very exciting innovation for timing users. Technologically, eLoran is quite different to GPS or the future Galileo system and so will not be compromised or impacted by the same interference or signal blocking problems associated with satellite PNT systems. In fact we have shown that the signal can penetrate buildings and street furniture which means that the telecom industry may have a viable alternative and/or augmentation to other edge timing technologies such as GPS or the emerging packet timing technology IEEE 1588v2. “

He added “We still have a lot of work to do evaluating the availability, integrity, and continuity of the eLoran signal, but early tests have proved very encouraging. We are keeping a 24x7 watch on the Anthorn timing signal using our SyncWatch web enabled data gathering and monitoring system. This system will revolutionise the way we bring timing to the edge of professional telecom networks and will be particularly useful for Wi-Max and GSM Base Stations and may, in time, become cost-effective for the emerging domestic audio/visual/femtocell technology markets. “

Chronos has also implemented an eLoran information page at http://www.gps-world.biz/eloran/index.php which will be kept up to date with breaking news on the technology and product developments as they emerge.”

About Chronos Technology

Chronos Technology Limited is the GNSS and RF components specialist for designers and products in the professional communications, military and electronics industry.  Chronos is also a specialist provider and system integrator of technical solutions for synchronisation, time of day and remote monitoring applications.  For more information visit www.chronos.co.uk or www.gps-world.biz