Talk:Hyperbolic navigation

Why no picture?

Why isn't there a picture? The first paragraph explains how it works. Now I want a picture to see the intersections.— Preceding unsigned comment added by 68.228.240.147 (talk) 08:14, 25 November 2012‎

I agree, a diagram would be very useful --Qwfp (talk) 17:33, 25 November 2017 (UTC)

I added a picture. It's made in GeoGebra, and you can fork from the Geogebra file here. pony in a strange land (talk) 08:09, 10 June 2019 (UTC)

It’s a great improvement to have the picture, but unfortunately the current illustration is in error. One (and only one) hyperbolic curve should intersect line L-AB (representing the time difference between Station A and station B), and the other hyperbolic curve should intersect line L-AC (representing the time difference between Station A and station C); however both curves are intersecting line L-AB (an impossible situation) and there is no curve intersecting line L-AC at all. If you could correct this it would be a great improvement. JT1956 (talk) 17:01, 25 September 2022 (UTC)

Erika

The Germans also had a hyperbolic navigation system during the war. I believe it was code-named Erika and was developed in 1941... possibly before the "Gee" system described in this article. German page: http://de.wikipedia.org/wiki/Erika_%28Funkfeuer%29 — Preceding unsigned comment added by 193.208.9.13 (talk) 20:58, 1 October 2014 (UTC)

Is there a contradiction in explanation?

"One of these stations, called the "secondary" is also equipped with a radio receiver. When this receiver hears the signal from the other station, referred to as the "master", it triggers its own broadcast. (...) Consider a portable receiver located on the midpoint of the line drawn between the two stations, known as the baseline. In this case, the signals will, necessarily, take 0.5 ms to reach the receiver."

If the second signal is delayed be waiting for the first signal, wouldn't there be already a delay at the midpoint? --178.42.3.78 (talk) 13:49, 2 May 2017 (UTC)

Added Example Subsection

Added Satellite Navigation Systems as examples of hyperbolic systems. This is well-known to specialists, but not beyond. See references and Global Positioning System. Quoting User-satellite geometry "Although usually not formed explicitly in the receiver processing, the conceptual time differences of arrival (TDOAs) define the measurement geometry. Each TDOA corresponds to a hyperboloid of revolution (see Multilateration). The line connecting the two satellites involved (and its extensions) forms the axis of the hyperboloid. The receiver is located at the point where three hyperboloids intersect.[62][63] It is sometimes incorrectly said that the user location is at the intersection of three spheres. While simpler to visualize, this is the case only if the receiver has a clock synchronized with the satellite clocks (i.e., the receiver measures true ranges to the satellites rather than range differences)." NavigationGuy (talk) 14:17, 22 December 2018 (UTC)

Right - if I understand correctly, GPS is a hyperbolic navigation system. That suggests that the lead-in sentence, that hyperbolic navigation is obsolete, is simply incorrect. Jordan Brown (talk) 17:41, 14 January 2021 (UTC)

The current illustration has a major error.

Unfortunately the current illustration has a major error. One (and only one) hyperbolic curve should intersect line L-AB (representing the time difference between Station A and station B), and the other hyperbolic curve should intersect line L-AC (representing the time difference between Station A and station C); however in the current illustration both curves are intersecting line L-AB (an impossible situation) and there is no curve intersecting line L-AC at all. If the creator of the illustration could correct this error it would be a great improvement. JT1956 (talk) 10:33, 12 October 2022 (UTC)