A 212Kb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE
The 53rd Civil GPS Service Interface Committee (CGSIC) took place in Nashville September 16-17, 2013. In layman’s terms, this is the meeting where the military side of the government meets the civilian side. The meeting has always been free and open to anybody. It is particularly valuable to precision users, surveyors included, who want to see where GPS is heading. This meeting was especially significant because September 16th marked the 30th anniversary of President Reagan’s Presidential Directive on GPS availability after the Soviets shot down Korean Air Lines flight 007 carrying 269 passengers and crew.
Giovanni Sella from the National Geodetic Survey (NGS) reported that CORS will make the transition from GPS-only to GNSS (GPS+GLONASS) on October 1. OPUS Projects is close to release. (Watch for a great article about it in an upcoming issue, complete with a step-by-step video.) CORS now has nearly 2,000 stations, but with some exceptions, new stations are only being added if they are at least 70 kilometers away from an existing station.
The constellation continues to perform incredibly well, with 31 healthy satellites on orbit, with four more in residual status, and one in test status. (Only 24 are needed to consider GPS in full operational capability.) More signals are coming: 11 satellites are currently broadcasting L2C; four are broadcasting L5; and the first GPS III satellite in 2015 will broadcast L1C. At the 2012 meeting, the buzz was all about LightSquared. This year it was evident that the GPS community is still wary of threats against the GPS spectrum. The constellation is somewhat dogged by its own success, as future launch plans are dependent on forecasts of existing satellite life. The Air Force has even considered the simultaneous launch of two satellites as a way to cut costs.
In one of the many interesting presentations, Rick Hamilton, CGSIC Executive Secretariat of the U.S. Coast Guard Navigation Center, made the case for requiring the use of the National Grid—already on many map products, including FEMA’s—for catastrophic incident search and rescue (SAR) operations. Hamilton said the 911 system is based on addresses, and in floods or hurricanes, when landmarks and signs are washed away or covered, rescuers lose reference points. It stands to reason that, like surveyors, ground-based rescuers can benefit from the same knowledge of lat-long or geographic coordinates. Hamilton also spoke about routing mistakes that had been made by confusing degrees minutes and seconds with degrees and decimal minutes, and stressed the need to speak the words "degrees", "minutes", and "decimal".
A 2011 report estimated nearly $70 billion in direct economic benefits from GPS, and more than 3.3 million jobs that rely on GPS technology. Unfortunately, many familiar faces were missing from this year’s meeting, due to the current government sequester and lack of funding for travel. For those who were able to attend, as always, meetings like this and the cross-pollinating interface they provide is what make possible the improvements in the marvelous GPS utility we enjoy.
Marc Cheves is editor of the magazine.
A 212Kb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE