# Making sense of values that decrese less and less as distance increases

I'm trying to come up with some formula to translate signal loss to distance.

Distance from Transmitter = x Signal loss = y

x=0 y=0
x=10 y=11.6
x=20 y=20.2
x=30 y=25.9

As you can see there is not a linear loss of signal as you travel in 10 meter steps away from the transmitter.

Is there some kind of equation that I can plug the signal loss into that will give me a rough estimate of the distance away from the transmitter I am?

Many Thanks, Code

-
It's hard to tell with so little data, but a guess is that it could be modeled with a power function. It's somewhat close to $y=2.14\cdot x^{0.74}$. –  Jonas Meyer Dec 18 '11 at 19:44
So y = 2.14 * x to the power of 0.74? –  Code Dec 18 '11 at 22:51
It makes more sense to try to figure a formula for what is left. What is the total signal? Is it 100? Any decent formula for loss should tend to that value as the distance tends to infinity. –  fedja Dec 19 '11 at 0:04
Code: What you wrote in your comment is ambiguous. The formula I gave matches the few points you gave somewhat closely, but there is far too little information given here to tell whether it is likely to be reasonable beyond that. –  Jonas Meyer Dec 19 '11 at 0:58
Yes, it signifies that you need to multiply 2.14 by the 0.74-th power of $x$ but, as Jonas and I remarked, this formula cannot hold for long beyond 30 and if we knew the total strength(=the maximal possible loss), we would come up with something more realistic. To know what exactly you call "the signal loss" would be useful as well. And to have a few more measurements would be great too. –  fedja Dec 19 '11 at 12:51