Out in Front: Welcome to Accuracy Anonymous

October 1, 2010  - By 0 Comments

The following was delivered as an invited presentation at the Civil GPS Service Interface Committee plenary session, held September 20 in Portland, Oregon.


Hi, my name is Alan, and I’m an accuracy addict.

I got my first taste of accuracy back in 2000 when I started at GPS World, and discovered the vast range of very advanced things that people were doing with the signals of the Global Positioning System.

This filled me with a great feeling of elation, expansiveness, and effectiveness. I can position anything. I can track anything. I can go anywhere, and know where I am. I can direct something else to go somewhere, and have it hit exactly on target. I can examine the minute movements of the earth, the swaying of skyscrapers, the moisture content of the atmosphere, and I can know all.

I began to feel the illusion of omnipotence — of power over all.

The more I found out about accuracy, the more I used it, the more addicted I became.

Very early, I learned that advanced practitioners, such as some of the people in this room, had developed ways of taking two GPS signals, not just one, but two signals, including one that they weren’t even entitled to use, and combining them, distilling them, refining them to produce an even more potent product: high precision.

High. I was getting pretty high. Almost as high as some of you.

Because we’re all in this together. In this room, we are all addicts. And when our supply of accuracy gets cut off, or restricted, or we learn that it might soon be diminished in some way, or even that its projected future rate of increase might not be as rapid as expected, or that it might not increase at all, it might just simply stay the same­ — well then, we get upset.

We want to get high precision, we want to stay high precision, and we want to get higher precision.

We may have a problem with our accuracy habit.

It’s not just us, the highly educated, highly equipped, highly advanced users, with near-lifelong histories of accuracy use. Outside this room, outside this convention center and all who gather here this week, outside our offices and labs, the great unwashed masses are getting their first taste of low-grade accuracy. With their cell phones or smart phones, maybe 50-meter, maybe 15-meter, maybe even 5-meter accuracy.

They’re liking it, that first taste. Once they learn how to exploit it, and learn that higher accuracy is possible, they’re going to demand it.

And some enterprising young engineers are going to build a high-powered LBS app that needs high accuracy, just like other new apps need broadband or WiFi or 3G or 4G. If the capability exists, someone wants to make money off it.

We may be raising a generation of monsters, who will absorb our habit into their bloodstreams and into their lifestyles.

Things might get ugly. We know they’re going to change, altering the landscape in ways we may not recognize.

I’m not talking about just the social landscape, the way accuracy users behave. Not just the user segment. I’m talking about the way accuracy is produced and administered. I’m talking about

the supply of accuracy, the supply of a substance that is in high demand and to which an increasing number of people are becoming addicted.
I’m talking about the ground control segment and the space segment.

Ultimately, I’m talking about who makes the decisions, who funds the decisions, who enacts the decisions, and who enforces the decisions about how much accuracy can and will be produced.

Today, we know, or think we know who those people are: the GPS Wing, the Air Force, the Department of Defense, the Administration of the U.S. government. We may think we know that those same people will be in charge tomorrow.

I’m not so sure. Revolutions have happened before.

I don’t mean to be U.S.-centric. The same developments are taking place, perhaps a bit lagged, in Europe and Russia and China. When the great mass of the Chinese market gets into using accuracy, gets the habit, you’re going to see some effects.

Returning to the United States, simply because it has the most known and most established of these systems, it is not inconceivable that some Tea Party-like movement, a groundswell should roll right up to Washington, into Congress, and say:

“Higher accuracy is possible. We are paying for GPS with our taxes, and we want you to spend that money producing and supplying us with a higher grade of accuracy. Don’t give us this talk of responsible stewards. We are calling the shots now. Just do it. Revise the ICD. Up the ante.
“Give me accuracy or give me death.”

Ladies and gentlemen, I have expanded, exaggerated only slightly, and perhaps exploded the old dictum that I’ve heard attributed to Charlie Trimble, I don’t know who first said it, but it bears repeating and repeating often: accuracy is addictive.

Indeed it is. I’m here to tell you.

I was asked to give you a user perspective. I’ve chosen what is today a relatively small user segment, but a very real one, and a growing one. And most important, one that augurs for the future.

Perhaps the scenario I just imagined for you exaggerates a bit. Perhaps. I am consciously trying to push further out the boundaries of our thinking.

We’ve been waiting, some of us, for a long time for the mass market to get involved in GPS. This is now happening, bit by bit. But it has not yet fully happened. When it does, great changes will come. When LBS figures out the key to making money out of location, you’ll see changes you can’t imagine today.

I started to become aware of how pervasive and how strong accuracy addiction has grown when we experienced a succession of anomalies in the GPS constellation over the last year or so: SVN-49, the last IIR-M satellite; carrier-phase anomalies detected on SVN-48; and now SVN-62, a small variance in the L5 signal on the first IIF. “The signal variation results in no more than a 5-centimeter error with a predictable periodicity of about six hours.”

In each case, GPS performed within spec, and some therefore viewed these issues as non-issues. “What seems to be lacking is context: what relevance their findings on unspecified and unrequired signal characteristics really have to do with the real-world GPS IIF mission and requirements.”

I’ve repeated here two printed quotes in the magazine; offline, the point-counterpoint discussion grew a good deal more inflamed. Passions run high when the supply and quality of accuracy appears in question.

This might seem a minor flare-up today, off in a corner of the field: specialized scientific research spatting with industry giants and their military-industrial complex benefactors.

But today’s developing applications in aviation, ground transportation, structural monitoring, machine control, infrastructure, and more use techniques such as carrier phase that are not governed, are not even mentioned in the GPS ICD.

When LBS gets figured out, and high-accuracy LBS and vehicle navigation and crash avoidance become regularly supplied commercial services, when the dependence of financial and communications infrastructure on high precision becomes fully understood and appreciated, then you’ll see some large corporate money that has become accuracy-addicted. Imagine this room in another few years, with GM, Ford, Google, Microsoft, AT&T, and Verizon attending and very interested, very much so, in aspects of user accuracy that are not currently addressed in the ICD.

This community will change. Its needs will change. Balances of power and funding will shift. Are we prepared for that? Are we prepared to be surp
rised? Or are we prepared only to be left behind by tides of change, to become obsolete?

This article is tagged with and posted in From the Editor
Alan Cameron

About the Author:

Alan Cameron is editor-in-chief and publisher of GPS World magazine, where he has worked since 2000. He also writes the monthly GNSS System Design e-mail newsletter and the Wide Awake blog.

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