TAG: Loran

In defense of PNT: Multi-GNSS to the rescue

May 11, 2016By
An artist's concept of a GPS IIR-M satellite in orbit (courtesy of Lockheed Martin).

For more than 41 years, many of us who were there in the beginning have been discussing the attributes, capabilities, enabling features and shortcomings of GPS and other space-based PNT (position, navigation and timing) systems. You have likely heard most of them; historically they go something like this: The signal is weak. The signal is easily jammed. The signal can be... read more

World dodges GPS bullet

February 24, 2016By
The plot shows how the anomaly event impacted one GPS timing receiver during the day. (Courtesy of Chronos Technology)

It happened in the blink of an eye. Less than a blink. Far less, actually. Slightly more than one one-thousandth of an eye blink, according to calculations. In that amount of time, one of your eyelashes traverses 10 micrometers on its journey toward your lower eyelid. And yet it was long enough to throw computers and communications systems around the... read more

This article is tagged with , and posted in GNSS, Opinions

You be the judge: To eLoran or not?

December 16, 2015By

Readers of GPS World, its e-newsletters, website — and all interested PNT parties — are invited to register their opinion in the current poll at gpsworld.com/janpoll. Should the U.S. government install a full eLoran network of broadcast stations to back up GPS in case of jamming, interference or other emergencies? Yes. No. More study is needed before answering this question.... read more

This article is tagged with , , , , , and posted in Latest News, Survey

NDGPS Destined for the Technological Boneyard

August 26, 2015By
"MARC AEM7s at BWI" by Ryan Stavely - Georgia_Trip_001. Licensed under CC BY-SA 2.0 via Commons.

Let us not exaggerate — nor prematurely announce — the death of a subsystem. However, the demise of the U.S. Nationwide Differential GPS (NDGPS) network can be confidently foretold. Although a Federal Register notice dated Aug. 18 merely seeks public comment on plans to shut down a large portion of NDGPS, the handwriting is on the wall. Once having writ,... read more

Bill Supports eLoran as GPS Backup

March 27, 2015By

A bi-partisan group of legislators led by Congressman John Garamendi (D-Calif.) has introduced a bill that would require the U.S. Secretary of Defense to establish a backup for GPS within three years using eLoran. The National Positioning, Navigation, and Timing Resilience and Security Act of 2015, H.R. 1678, was co-sponsored by Congressmen Duncan Hunter (R-Calif.), Peter DeFazio (D-Ore.), and Frank LoBiondo (R-N.J). Garamendi is the... read more

Out in Front: Epic Fail

July 1, 2014By

Sometimes the patient has to get sick in order to get better. The eruption of a malady leads to identification of an underlying condition; appropriate treatment can then be devised to cure the body of its ills. Sound like House, M.D.? As a variant on this plot line, the patient can know full well what is wrong deep down inside,... read more

This article is tagged with , , , , , and posted in From the Magazine, Opinions

eDLoran: The Next-Gen Loran

June 28, 2014By
vw-O2

Potential GNSS Back-up Improves to GPS-Level Accuracy
A new enhanced differential Loran system demonstrates 5-meter accuracy not achievable by the current DLoran system, and requires less expensive reference stations. A prototype tested in Rotterdam’s Europort area uses standard mobile telecom networks and the Internet to reduce correction data latency — a key source of error — by one to two orders of magnitude. read more

This article is tagged with , , , , and posted in Featured Stories, Transportation

eDLoran Surprise: European Navigation Conference 2014

May 14, 2014By
Shipboard DLORAN receiver installation (orange boxes on rails).

At the ENC-GNSS Conference in Rotterdam, we delved into actions necessary to officially use EGNOS (giving me déjà vu from WAAS’s early days), heard sage words from Brad Parkinson, the father of GPS, and, on the last day, saw amazing proof of a claim many of us initially thought was outrageous —that differential (DLoran) with modern monitoring can result in consistent horizontal accuracies approaching five meters on a moving platform. read more