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Usually, when you're trying to find a source of whatever signal, you move around the source and then calculate the position using triangulation. I'm specifically talking about low frequency signals, such as radio waves.

I was wondering what can make this process harder or completely impossible (the former seems very unlikely).
If there were two transmitters, would it be easy to tell that there are two and not one? Could the signal be dispersed unevenly in the area, making it appear somewhere else than it is?

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Are the two transmitters fixed or moving in the scenario you are interested in? –  paisanco Jun 20 at 1:51
    
They are fixed transmitters. But it's a good point that if the object moves the things get harder. –  Tomáš Zato Jun 20 at 1:53

1 Answer 1

There are many techniques for radio direction finding, such as triangulation as you mentioned, and also time difference of arrival (TDOA) and other techniques.

Some of the factors that can affect the accuracy of signal location are:

  • How many locations the measurements are taken at and the resulting position ambiguities (this varies by technique used e.g for TDOA, with 2 receivers the source could be anywhere on a hyperbola, you need at least 3 to get a fix)
  • Uncertainties in the position of the receivers

  • The directional sensitivity of the receiver -how well the antenna can resolve angles

  • The directionality of the signal source itself - it may have different strengths in different directions

  • Multipath, where signals get refracted in the atmosphere or reflected off of objects like trees and buildings, leading to multiple signals arriving at different times

  • Source motion

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What about signal intensity changing in time? Would that need to be calculated? –  Tomáš Zato Jun 20 at 2:48
    
If known, yes that could influence things as well. Is this the level of detail you were looking for? –  paisanco Jun 20 at 2:53
    
I'm, in fact, looking for the level where triangulation is impossible. But I doubt such level exists. –  Tomáš Zato Jun 22 at 9:24

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