New GPS Satellite Launched

zonker writes "A U.S. Air Force Delta 2 rocket launched a new GPS satellite today to add to the collection of 27 up there. This new GPS satellite is one of seven now in orbit as a replacement for an earlier generation of GPS. May be of interest to the GPS folks out there."

Big News Item!

[loraksus]

Though try using the Russian GPS system if you don't want local "fuzziness" around certain areas (Washington DC)

GPS errors

[drDugan]

I learned some stuff about GPS from a co worker who codes applications for Palm pilots that integrates GPS data. Until just recently (last May) all non-military uses of GPS integrated intentional ERRORS in the signals, making it hard to produce accurate locations from the GPS signals.

This sentiment is mirrored here:
http://www.sbcmag.net/texis/scripts/vnews/newspape r/+/ART/2000/11/01/3a00633f9 [sbcmag.net]

seems sort of shifty if you ask me.

Re:GPS errors

[Throw Away Account]

"sort of shifty"?

It wasn't a secret the military tried to keep; they told you straight out that the civilian channel had deliberate inaccuracies in it to degrade its military value for potential hostile powers.

Hardened military targets (bunkers) and mobile armored targets (tanks) are very hard to destroy with accuracies of 100 meters; they are very easy to destroy with accuracies in the single meter range. And hundred-meter accuracies were good enough for most civilian navigation, whether by hikers, boaters, or pilots.

And Clinton didn't lift the restrictions out of the goodness of his heart, either. It's just that techniques that compared the GPS-reported and known actual coordinates of landmarks allowed for correction of civilian data to military-level accuracy*. So separate levels of access were no longer benefiting national security.

*Ironically, the Coast Guard pioneered these techinques, since they weren't given access to the military data.

Re:GPS errors

[sales_worldwide]

The big joke is that the errors were never meant to be on full time, only during wartime. However, during the Gulf war, the errors were turned off! (apparently the military were using civilian GPS units since they had trouble making enough of their own that decrypted the "jitter")

Re:GPS errors

[isorox]

Wasnt there a bond film that revolved arround this?

Is it me or are we coming too reliant on this?

[Reedi]

The following is not a joke. Minor changes have been made to protect the privacy of those too stupid for words.

I was sysadminning for a major UK law firm about 18 months ago when I learned of a case we were working on for an insurance company
It seems the insurance company were unwilling to pay for the loss of a 60000 tonne bulk cargo carrier which had run aground in the Carribean (in broad daylight, on a flat calm sea with unlimited visibility) because the captain was watching the GPS and not what was directly in front of the bows.

Needless to say no-one involved was very happy

Ian

Re:Is it me or are we coming too reliant on this?

[corran__horn]

Couldn't we solve this by installing sensors on the front of the boat to detect reefs and alert the captain? This might solve some of the problems.
Could we just make sensors that detect mental function in the Captains of ships? That would have prevented the exxon valdez and many other disasters.


If people can connect to one another even the smallest of voices will grow loud.

Re:Is it me or are we coming too reliant on this?

[Gehenna_Gehenna]

Problems like this are caused by poor navigation and too much relience on technoledgy. Even the best tecnoledgy fails. I was a navigator for 3 years in the US Navy. We DID have the sexy GPS decription going on, but we also verified our position every hour using radar, even stars. Occasionally we would cover up the GPS (during drills) and see how well we navigated using an old sextant. When professionals get lazy these problems occur. GPS is a great tool, but only one of MANY tools needed to safely navigate at sea.

No e-break slides with a tanker

[sideshow]

Ships have all kinds of stuff like this. Problem is a ship can't lock the breaks and stop in the nick of time. More like: Captain: Oh fuck, better brace for impact in the next 2 or three minutes.