Ocean Navigator Communications Newsletter #10

Galileo Underway in Europe

As I promised last time, here are some interesting tidbits about Europe's
forthcoming Galileo system. Satellite navigation is not new to the European
Union, which recently fired up the first phase of their program, the
European Global Navigation Overlay Service system. EGNOS is essentially the
European counterpart to the United States' Wide Area Augmentation System.
Both WAAS and EGNOS supply a supplementary correction signal to offer GPS
users more accuracy and precision.

Galileo is the second phase of Europe's satellite navigation program. It
will be a new satellite navigation system independent of the U.S.-controlled
GPS constellation. The theory goes something like this: GPS was designed
initially by the U.S. military (Department of Defense); it has since been
relied upon as a primary location service for many non-military services;
although the United States has pledged to continue to support civilian use
of GPS, the U.S. military can selectively deny the GPS signal in certain
theaters of operation; Europe has no control over when and where the GPS
signal is available or unavailable. Though we've traditionally been the
closest of allies with most of western Europe, in the interest of their own
security and independence, they've decided to build an entirely new
constellation of satellites to provide positioning information.

The idea of a non-U.S.-controlled GPS service is not a new one. In the
waning years of the Cold War, the Soviet Union (later Russia) was hard at
work developing Glonass -- a Russian-controlled satellite navigation system.
Though the design was complete and operational, they never successfully
launched enough satellites to provide sufficient coverage for most uses.
There are still a few Glonass satellites flying around in space, but not
enough to be terribly useful.

Some say that the creation of an entirely new system (Galileo) to provide an
(almost) identical service to an existing system (GPS) is a waste of money.
The U.S. military in particular is not very enthusiastic about Galileo.
However, there are many good reasons for proceeding with the project.
Scientists, geologists, surveyors and the like are eager to see Galileo
developed. In addition to the planned increase in precision, a redundant
system to rely on and compare with is an immensely useful tool. Think back
to the old carpenter's adage, measure twice, cut once. With Galileo and GPS,
measuring twice will be an easy thing to do.

Some of the European countries are concerned that one day they and the
United States will be on opposing sides of a conflict and the denial of GPS
signals to certain areas could be devastating in both a military and a
civilian industrial capacity. Should they build trains that rely on GPS
positioning and run the risk of not being able to run trains into or out of,
say, Croatia? France in particular seems to be rallying behind the cry
"independence at any cost."

And what about integrity? In the scientific sense, integrity is the notion
of letting you know that a system is operating as planned. In other words,
if your GPS receiver were giving you a faulty position, how would you know
about it? Galileo plans to have an integrity signal built in -- think of it
like this: a green OK sign will be showing if the signal is a good one, and
a red not-OK sign might indicate a faulty reading.

As for paying for the $3 billion price tag, lots of proposals have been
developed, including the idea of having sophisticated users pay for advanced
services. So a hand-held civilian Galileo receiver might still be able to
have access to a free signal, but a precision surveying Galileo receiver
might require a paid subscription.

As for use on the water, what will Galileo bring? I would predict that as we
approach the planned 2008 operational date for Galileo, we'll start to see
dual-system receivers become available initially at a higher price tag
targeted primarily at users that require a high degree of precision and
integrity (think aviation, surveying and such). Before long, these receivers
will be available at reasonable enough prices that they'll become
commonplace on many recreational boats -- why not have a backup system if
it's not all that expensive?

We've come a long way since the first Galileo 500 years ago! If history
repeats itself, it sure gets improved along the way.

- Dan Piltch
dpiltch@MarineComputer.com