Tuesday, May 31, 2005

WFB on GPS

More than 20 years ago, and early in my career, I focused on technical and regulatory issues surrounding radio-determination satellite systems. In the early 80s, the Global Positioning System (GPS) constellation had just been completed (18 out of 24 satellites in orbit), and the DOD was concerned that the Soviets might use GPS signals to aim their ICBMs more precisely at the third button down on President Reagan's starched white shirt. DOD thus degraded the GPS signal to deny precision to the Ruskies. My client proposed to offer more accurate civilian service. A few years of lobbying later, we won an FCC license just when President Reagan committed to ending GPS degradation, a policy ultimately implemented in 2000.

When he isn't writing, thinking, hosting talk shows, and founding and publishing the National Review, William F. Buckely is an amateur sailor. As such, he's a consumer of positioning services, and while reading his literary autobiography this weekend, I stumbled across Buckely on GPS:
It is proper to rejoice when reflecting on GPS, but there is a menacing factor in the enterprise, which is called Selective Availability. This means that when the Pentagon feels like it, which is. . .when it feels like it, the signal is degraded, up to three hundred meters. In a fog, that could make the difference between finding the channel entrance and hitting rocks. Why the "dithering," as it is generally called? Answer: national defense. But really, we have a geostrategic affection. The enemy is not going to target our hardened silos by GPS--they'd use inertial guidance, as we do. Moreover, the only world power capable of that kind of aggression right now is still Russia, and the irony here is that they have developed their own GPS system, called Glonass, and it is not degraded, giving the navigator real accuracy. A defense against unreliable signals is the system called Differential GPS. What we have here is beacons scattered along coastal waters. A fifteen-million-dollar Coast Guard operation designed to frustrate the Defense Department. But to tune in on DGPS you need--yet another receiver. As long as Loran is still around, we have the option of dropping GPS and going loran when in menacing areas. There is talk of dropping loran, an event that would leave us at the mercy of an unreliable GPS. If that happens, the only thing to do is exercise selective political availability at the polls.
William F. Buckely, Gulf Stream Musings, reprinted in Miles Gone By at 166 (2004).

Of course, the American electorate did just that in 1992. By then, my client was long gone; bankrupt, its license revoked. De mortuis nil nisi bonum.

4 comments:

@nooil4pacifists said...

True, but almost anything's better than tracing those hyperbolic loran curves.

@nooil4pacifists said...

Cogito subito:

Mistake?

Anonymous said...

My usual line of work, cellular optimization, involves driving around with a laptop computer displaying call data and GPS map data. For about a month after 9/11 the map showed me driving on the sidewalk. I have no idea what security value that imposed inaccuracy provided.

@nooil4pacifists said...

Triticale:

Hail telecommer, well met.

I never could get GPS accuracy under about 10 yards, never mind street-vs-sidewalk. Obvously, ten, or even fifty, yards don't alter the risk. I gather that GPS's former precision returned in November 2001?