Network corrected real-time is a technological approach to high precision GPS/ GNSS positioning that has been theorized about, studied, experimented with, and implemented in various academic, scientific, and commercial forms for nearly a decade.
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Amidst the cherry blossoms that signal spring and attract hundreds of thousands of visitors to Washington, D.C., mapping and GPS professionals also got together for the spring meetings of CGSIC and MAPPS.
CGSIC
At Civil GPS System Service Interface Committee (CGSIC) meetings, the military side of the GPS community meets the federal civilian side. Among the discussions about the future of GPS and GPS policy, the near-term effects on the precise user community can be discerned. The spring meeting yielded good news for GPS users. First, after four years of negotiations, the disagreements between the U.S. and the European Union over at least one of the proposed Galileo signal structures has, at least for now, been ironed out: at a meeting in Brussels in February, an agreement was made to use the same frequency on L1. This will pave the way for receiver manufacturers to build boards that work all over the world instead of building different boards for use in Europe and the U.S. Previously, the EU had indicated that it would use a different signal structure, one that would have interfered with GPS military signals, and enormous pressure was brought to bear on the Europeans due to our common defense needs. Given the current political disagreements between Europe and the U.S., the announcement was good news indeed.
Those of you who recall the early-day nighttime schedules that were required for making GPS observations would agree that the CGSIC announcement of the new GPS L2C signal was another source of good news. Over the years, as we have watched the usefulness of GPS increase as more satellites were added I perhaps was not alone in assuming that we would need many satellites with the new signals for them to be useful. But this is not so. For receivers equipped to receive it--as of the meeting, Trimble and Javad--the new signal will be useful from the first satellite on. Tom Stansell also pointed out that by 2011, 18 satellites with L2C will be aloft, just in time for the next Solar Max. Stansell added, "The next Solar Max might be more severe that the one we just went through, and L2C will aid in ionospheric corrections." Additionally, L2C will work with existing antennas, thereby making archived measurements still useful.
The agreement with EU paves the way for the possibility of as many as 60 satellites broadcasting the same signal. Larry Hothem from USGS pointed out that the existing L1C/A signal will not be affected by another new signal, L1C. L1C is but one of a whole host of new signals that will be incrementally implemented as we move toward GPSIII. In addition to the existing L1C/A, L1P/Y and L2P/Y signals, future new signals will include L1M and L2M (M=military, C = civilian), L2C, L1C, and L5. These last three are the new signals for us. Hothem indicated that future signals will contain as much as three times more power, making them useful for quicker signal acquisition and working under tree canopies.
In an NDGPS report, we learned that 81 sites are now operational, providing 87 percent of CONUS with single-station coverage. Dual-coverage exists for 55 percent of CONUS. Eight more stations have been funded, and even though funding has been abysmal, enough existing GWEN sites are available that twice that number could be installed if there was funding. With the installation of nine more stations by the end of 2005, nationwide single-station coverage will exist.
MAPPS
The Management Association for Private Photogrammetric Surveyors (MAPPS) exists to keep its members informed of upcoming contracts for their services, assure adequate funding for important surveying, mapping and geospatial programs, and hold the federal government's feet to the fire regarding privatization of federal work. The MAPPS conference brought together representatives of all the major federal agencies that contract work to the private sector, including BLM, USDA, E PA, USGS, NOAA, the Census Bureau, NASA, Department of Homeland Security (DHS), NGA (National Geospatial-Intelligence Agency, formerly NIMA), Naval Facilities Engineering Command, and Corps of Engineers. A common theme throughout the day was good news, bad news: a higher percentage of money is being made available to the private sector, but budgets are shrinking. Of these agencies, DHS appears to be the most promising. Ryan Cast, DHS Chief Geospatial Information Officer, said that the budget ($5 million in FY05) will swell to $1 billion for the years FY06 through FY10. Of this, 30 percent will be funneled to the private sector.
MAPPS continues to vigorously pursue not only work for its members (including aerial photogrammetry, commercial satellite remote sensing, and GIS firms), but also funding for critical programs such as USGS mapping, and NOAA mapping, charting and coastal services. Barb Ryan from USGS compared national mapping efforts to the interstate highway program started in the 1950s: this is something that the U.S. government should do because it benefits everybody. Of particular concern to MAPPS is:
• competition from FPI--the federal prison industries (FPI) and its foray into mapping-related services such as G I S and CADD. In the view of MAPPS, the use of convict labor allows FPI to compete unfairly.
• foreign outsourcing--sending critical infrastructure data offshore for mapping. Of course, balancing the data needs of our own development industry against the desires of terrorists to use the information against us will require careful consideration.
• homeland security-- the official MAPPS position is "It is critical that federal, state and local government officials have a current, common, consistent and compatible GIS to protect critical infrastructure, plan emergency preparedness and execute emergency response."
• departments of transportation-- MAPPS says, "Stronger action by Congress and FHWA is needed to reverse the trend toward high-cost, low-efficiency monopolies within state departments of transportation."
Additionally, MAPPS fights a constant battle against legislation that would repeal the FAIR Act, as well as other existing law that requires the government to utilize the efficiency and innovation of the free market. To this end, the second day of the meeting was devoted to meetings with legislators on Capitol Hill to present the concerns of MAPPS members.
Saluting a Mentor
In this issue, we travel to Texas to present the second in our new series that focuses on The Fabric of Surveying in America. Austin resident J. Stanley Coalter discusses the "wrinkles" in the fabric that make Texas unique. Most of us are familiar with the two basic surveying systems in the United States: colonial metes and bounds and the Public Lands Survey System. But Texas has its own form of metes and bounds surveying, and except for West Texas and the Texas Panhandle, parcels resemble the odd-shaped tracts that are common on the East Coast.
I'm also proud to say that Stanley is the person I credit most of all for encouraging me to become a licensed surveyor, and it was in Texas in 1984 where I was granted my first license. Prior to our association, the most attractive thing about surveying to me was the technology that began transforming our profession in the late 1970s. But it was Stanley who opened my eyes to the fascinating legal aspects of surveying, both in public land states and in the Texas metes and bounds system. Fortunately, Stanley is a continuing education provider in Texas, so his knowledge is being passed on to future generations. The photo of the two of us was taken at the time of the ACS M / TSPLS show in Galveston a few years back.
Mind Candy for Surveyors
In his new column titled "Everything is Somewhere," licensed surveyor and writer Angus Stocking offers our diverse group of readers something he calls "mind candy for surveyors." The column will break away from the conventional topic of surveying, and venture into subjects that, as Stocking puts it, "are bound to appeal to the curious, spatially gifted, unconventional intellects that surveying attracts." Treat yourself to the first of his articles, which begins on page 42.
Marc Cheves is editor of the magazine.
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Editorial: Surveyors Get the Point
For me, the 6th annual ESRI Surveying and Engineering Summit represented a sea-change. While earlier meetings I attended were designed to attract surveyors into the world of GIS, the trend has taken hold and surveyors everywhere are busy incorporating GIS into their work flows. I like the way .... Read the Article
Point to Point: Can Retracements Be Confidential?
Do your clients have a right to expect that the survey you conduct for them will be confidential? Let's assume for a moment that mandatory survey recording laws did not exist (and indeed, they do not exist in most areas) and that no other obligation to divulge the results of the .... Read the Article
WowFactor: TPC Desktop 2008 Global Background Clearing
TPC Desktop 2008 is all about making it easier to work with your survey data and drawings. It's about doing less work and getting more done. Their new Global Background Clearing is a good example. We put a lot of information on drawings. Take a typical ALTA or site survey-- they can ... Read the Article
Wildfire Maps Keep Agency Missions Blazing Forward
Blazing out of control wildfires have been sweeping across northern California this summer just as they did last fall in the southern region of the state and many times previously, leaving in their path death and destruction. These fires are ... Read the Article
Applanix: Solutions for Mobile Mapping and Positioning
It's a given that Global Navigation Satellite Systems (GNSS) don't work everywhere, for example if the signals are sufficiently blocked by such things as tree canopy, or urban canyons. Because of the need to locate things everywhere, a great deal of .... Read the Article
RTN-101: Mapping (Part 14)
Much of what surveyors do is essentially mapping, and much of mapping is/could/ would/should be characterized as surveying. But what certainly raises the blood pressure of many surveyors is when one puts the two terms in the same sentence, as I have just done. The debate over.... Read the Article
The Marriage of GIS and Land Surveying (No Shotgun Needed)
Too often the GIS professional and the surveyor are at odds; a hoity-toity GIS guy looks askance at a muddy-booted surveyor who wants to pin him down on accuracy and ... Read the Article
Software Review: I-Site Studio 3.0 and 4400 Laser Scanner
It seems that every surveying magazine now overflows with stunning 3D images of everything from people, to cars, to historic landmarks, to infrastructure. Point clouds of intricate structures and shapes naturally captivate the geometrically adept mind. But what about the ... Read the Article
Product Review: SECO Poles and Prisms
Tired of prism pole slippage and non-adjustable prism pole bubble levels? Tired of tilting prism target assemblies that slip as you are walking back to the instrument or having to lift the prism pole out of the bipod ring, or not being able to adjust the "spring" out of ... Read the Article
Vantage Point: If Not Now, When?
June was a difficult month. A friend less than a year older than I am quickly succumbed to a resurgence of breast cancer. A colleague three years younger suddenly died of complications related to diabetes, although he had looked fine just a few months ago when I last saw him. Such events make ... Read the Article
Surveying `Da Situation: The Last Straw
It is bad enough that we've already had to endure months of election campaign rhetoric, but I read an article awhile back that was the last straw. I happened to be scanning the newspaper when I came across a piece reporting that the rock star Bruce Springsteen had ... Read the Article
• 15th Annual GeoTech - October 7-8, 2008, NOAA’s Auditorium and Science Center in Silver Spring, MD. Hosted by Potomac Region of the American Society of Photogrammetry and Remote Sensing and co-hosted by the NGS, 1 day of Workshops taught by experts, and 1 day of Technical sessions.,
• GITA's First Annual GIS for Oil & Gas Conference - Calgary - Nov. 6-7, 2008, Calgary Marriott Hotel, Calgary, Alberta, Canada. The GIS for Oil & Gas Calgary Conference will build on the momentum from GITA’s GIS for Oil & Gas Conference held in Houston, Texas, every September.
• GITA's “How to Financially Justify Your Geospatial Projects” Two-day Workshop - Nov. 13-14, 2008 in Denver, Dec. 11-12, 2008 in Tampa. All types of organizations now have a unique opportunity to learn from GITA’s landmark research project, “Building a Business Case for Geospatial Information Technology: A Practitioner’s Guide to Financial and Strategic Analysis.”
• Geography in Las Vegas - March 22–27, 2009. Join 8,000 geographers, GIS specialists, and environmental scientists from around the world in Las Vegas for the very latest in research, policy, and applications in geography, sustainability, and GIScience, during the annual conference of the Association of American Geographers.
• California Land Surveyors Association 2009 Conference - March 28-April 1, 2009, Hilton San Diego Resort (Mission Bay).
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, (707) 578-6016.
• SPAR 2009 - March 30- April 1, 2009, Hyatt Regency Hotel, Denver, Colorado. SPAR 2009 will focus on best practices for using 3D imaging technologies to design and deliver capital projects as well as operate, modify and maintain production, manufacturing and infrastructure assets.
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