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3 point navigation

Started by Hul Tytus November 19, 2021
   Anyone know the method for calculating a reciever's position from the time 
difference between three rf pulse transmiters of known positions? This has 
apparantly been in use since the second world war but a description of the 
mathematics involved is hiding. Maybe a text on navagation methods?

Hul

On Fri, 19 Nov 2021 20:32:34 -0000 (UTC), Hul Tytus <ht@panix.com>
wrote:

> Anyone know the method for calculating a reciever's position from the time >difference between three rf pulse transmiters of known positions? This has >apparantly been in use since the second world war but a description of the >mathematics involved is hiding. Maybe a text on navagation methods?
Hyperbolic navigation. .<https://en.wikipedia.org/wiki/Hyperbolic_navigation> Joe Gwinn
On Fri, 19 Nov 2021 20:32:34 -0000 (UTC), Hul Tytus <ht@panix.com>
wrote:

> Anyone know the method for calculating a reciever's position from the time >difference between three rf pulse transmiters of known positions? This has >apparantly been in use since the second world war but a description of the >mathematics involved is hiding. Maybe a text on navagation methods? > >Hul
The old terms and tech (i.e. LORAN) have changed since WWII. Hyperbolic navigation is still with us, but with the advent of cellular and ADS-B, it's now called MLAT (multilateration), TOA, TDOA (time difference of arrival), or a multitude of other term. Note that the GPS system uses the flight time between the GPS receiver and the known positions of at least 3 GPS satellites. These should supply a list of buzzwords to research: <https://en.wikipedia.org/wiki/Multilateration> <https://en.wikipedia.org/wiki/True-range_multilateration> <https://www.sciencedirect.com/topics/engineering/multilateration> -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558
On Friday, November 19, 2021 at 4:32:40 PM UTC-4, Hul Tytus wrote:
> Anyone know the method for calculating a reciever's position from the time > difference between three rf pulse transmiters of known positions? This has > apparantly been in use since the second world war but a description of the > mathematics involved is hiding. Maybe a text on navagation methods?
The only parameter you can determine without a highly directional antenna is the difference in arrival time which places the transmitter on a hyperbola with two receiving antennas at the foci. Add a third antenna and you get intersecting hyperbol&aelig; which will resolve the transmitter's location to a point. But you are asking to locate a receiver from the time difference of arrival of known transmitters. Same problem with the transmitters at the foci. I believe this is the basis of locating a commercial aircraft based on the TACAN signal. The math is just algebra and trig, solving simultaneous hyperbolic equations. I think two baselines give you only two points as solutions and the remaining baseline resolves between those two. -- Rick C. - Get 1,000 miles of free Supercharging - Tesla referral code - https://ts.la/richard11209