It´s been about a year since I´ve touched on WAAS (Wide Area Augmentation System) with any depth, and a lot of things are happening on that front so I´d thought I&acite;d give an update. Also, look for a column on EGNOS (Europe´s version of WAAS) in the next month or two.

Whether you live in London, Lagos, Lisbon, or Los Angeles, when you are looking to buy a survey instrument, most likely you have a preferred instrument distributor in mind. Maybe it´s the local Topcon dealer. Perhaps your Leica dealer has served you well. Or you might prefer the Trimble dealer in your area. All of the manufacturers have distributors signed up around the world. Some operate on a regional basis, serving several countries, while others serve one specific country. I raise this point because of recent, significant changes in the U.S. distribution of survey instruments.

Ok, this column is supposed to be about high-precision GNSS, right? Well, who would have ever thought I?d be inclined to write about consumer GPS receivers? Certainly not me. Sometimes, I even speak rather condescendingly about those Wal-Mart GPS units because they seem to be mis-used so often in the survey/construction business

While 2006 saw two IIR-M satellite launches, look for double that in 2007. Even if new launches don?t improve the PDOP spikes, we?ll have more reliable hardware in orbit. The Big Mo is rolling.

I have something to say about our mainstay — GPS — and its troubles of late.