Subj: GWEN Towers
Date: 1/14/02 6:28:33 AM Pacific Standard Time

Now here's a guy on top of things!
I gotta run, but thought you might want to follow up on this.

Date: January 13, 2002 at 22:12:37


Got some good techie stuff for you sir r.e. GWEN towers.
First of all though, this is some pertinent info to understand the history etc.

Although the federally-provided NDGPS funding for this current fiscal year fell short, by about one-half of the amount requested, there is ample budget to begin the process of adding new broadcast stations. Fortunately, for New Mexicans, Albuquerque's Kirtland Air Force Base will be the site of one of the first newly-established NDGPS stations. We anticipate that the Kirtland station will be operational by April 2000. Under an exemplary cooperative effort, many government agencies are contributing to this program. The US Air Force is making available a de-classified / de-commissioned network of emergency communications facilities, the Ground Wave Emergency Network (GWEN). A total of 53 GWEN sites located around the country will be converted from their old communications configurations to real-time GPS reference station installations. Differential corrections will be broadcast, at around 300 kHz, from 90-meter-tall GWEN transmission towers.


The Nationwide Differential expansion is continuing to make progress. Funding for this year is about half of the administration's request. Single coverage expected in 2002 is now hoped for the year 2003. Last year, the Coast Guard’s Nationwide DGPS (NDGPS) implementation team was very busy refining the procedures for converting a GWEN (U.S. Air Force Ground Wave Emergency Network) site to an NDGPS site. To date, there are twelve sites that have been fully converted from their GWEN configurations to transmit DGPS corrections. These sites are located near Chico CA, Clark SD, Driver VA, Penobscot ME, Savannah GA, Macon GA, Whitney NE, Hudson Falls, NY, Billings MT, New Bern NC, Summerfield TX and Flagstaff AZ. The site at Appleton WA continues operation in its test configuration and the site near Hartsville TN increased its antenna to 299 feet.

So the old GWEN system was converted to be used for the new NDGPS system.
Nationwide Differential GPS

Here is the official .gov site for some good tidbits: