"triangulation"-- what does it mean?

[only_more_so]

I was being serious, Triangulation has been a mainstay of navigation and surveying for a lot longer than radio.

Another variation is to take bearings on two known points from an unknown point -- like sighting on lighthouses lighthouses or mountain peaks and drawing two crossing lines on a map/chart to determine your location -- a concept adapted to radio technolgy in the form of the network of LORAN (LOng RAnnge Navigation) navigation beacons the Navy and Coast Guard maintains even in this age of Satelite Navigation systems (which are really an extension of the LORAN concept.)

As for the political meaning, I really couldn't care less how that sector of society misuses it.

Actually, Loran works on an entirely different principle than triangulation, since the LORAN becons do not provide direction information, only time phase information. You actually need three Loran signals to identify a location.

I am sure my college professors would be so proud that the lessons they taught me are being used to dispute a tangential arguement on a sex website.

 

[rgraham666]

I am sure my college professors would be so proud that the lessons they taught me are being used to dispute a tangential arguement on a sex website.

It's strange where life takes you, isn't it?

 

[Pure]

Notice:

I think this thread, henceforth should be devoted to pets. The original topic as well as the navigational tangent are surely played out.

How's everyone's doggies and kitties?

 

[Weird Harold]

Actually, Loran works on an entirely different principle than triangulation, since the LORAN becons do not provide direction information, only time phase information. You actually need three Loran signals to identify a location.

I am sure my college professors would be so proud that the lessons they taught me are being used to dispute a tangential arguement on a sex website.

That sounds like the LORAN-D systems developed in the late sixties for precision aircraft navigation, (and blind bombing in Vietnam,) which was an entirely different system from the earlier analog LORAN/TACAN systems that provied only bearing (or bearing and distance information for TACAN stations.)

It also sounds a LOT like the way GPS works, which is a variation on triangulation that provides a three dimensional position fix by comparing time signals from three or more satelites.

However, Comm/Nav wasn't my career field and I only got the most basic explanation of the systems becaue they tied into the ballistic computer and tactical radar systems that I worked on, so I'll concede you probably know more about current LORAN systems than I do.

 

[only_more_so]

That sounds like the LORAN-D systems developed in the late sixties for precision aircraft navigation, (and blind bombing in Vietnam,) which was an entirely different system from the earlier analog LORAN/TACAN systems that provied only bearing (or bearing and distance information for TACAN stations.)

It also sounds a LOT like the way GPS works, which is a variation on triangulation that provides a three dimensional position fix by comparing time signals from three or more satelites.

However, Comm/Nav wasn't my career field and I only got the most basic explanation of the systems becaue they tied into the ballistic computer and tactical radar systems that I worked on, so I'll concede you probably know more about current LORAN systems than I do.

Yeah, I was talking about the modern Loran system. I believe the TACAN part was what provided the bearing and distance, the Loran portion identified position along a hyperbole.

I don't think I would classify GPS as triangulation, since you are effectively finding the intersection of four spheres of unknown radii, but with known difference in radii and known centers. If you have a synchronized clock, you can get away with three spheres since you then know the radii. Very similar to how they identify the epicenter of earthquakes, except that is more of a 2-D problem.

 

[Weird Harold]

Yeah, I was talking about the modern Loran system. I believe the TACAN part was what provided the bearing and distance, the Loran portion identified position along a hyperbole.

As implemented in the F4 Phantom, the TACtical Air Navigation system (TACAN) could use either TACAN or LORAN stations to provide bearing but only the TACAN stations had the Distance Measuring Equipment (DME) coding to provide both range and bearing. The Bearing funtion was essentially just automated Radio Direction Finding (RDF) and could theoretically get a bearing from any radio translmitter -- like a commercial AM or FM station.

I don't think I would classify GPS as triangulation, since you are effectively finding the intersection of four spheres of unknown radii, but with known difference in radii and known centers. If you have a synchronized clock,

GPS uses distance based triangulation. The first satelite provides a synchronises clock signal to reference the clock signals from the next three to five satelites -- the minute time differences in the synchronized clock signals induced by signal transit times (multiplied by C) give precise distances from each satelite to solve "side, side, side" triangle propblems for each pair of satelites and the GPS receiver.

Very similar to how they identify the epicenter of earthquakes, except that is more of a 2-D problem.

Earthquake epicener calculations give the depth as well as Lat/long, don't they -- that makes them 3D solutions (and almost exactly the same principles of triangualtion GPS uses.)

 

[trysail]

...identified position along a hyperbole.

Uhhh..., er..., ah..., unless you're exaggerating, would that possibly be a hyperbola?