How to mesure distance and angle

I'm looking a good method to determine the exact position of a broadcasting FM transmiter (88-108 Mhz), how can I determine or mesure angle from my receptor to the transmiter, with a minimal error?

I'm looking for circuits or schematics that can do this.

Thanks

Look for some info here http://www.rsd.de/
They are one of the best . But it is very difficult in urban areas .

This is called direction finding. For strong signals an antenna with two beams and a deep null between them is usually used. A loop antenna is probably the easiest to make. It has two nulls but you will know the approximate location of the station from their announcements or a listing of stations on each frequency.

You calibrate the angle by measuring the direction to a known station which will give you the error in your system. Then you subtract the error from the measurements on unknown stations.

Yeah , this one was used during 2nd world war .
Mentioned above company was producing such equipment . This method is used till our days in simple equipment . To find true direction 2 loop antennas in vertical and perpendicular position one to each other .

First you find angle by minimum signal - it could have 2 direction forward and backward due to loop antenna properties. Then (do not know theory well and may be incorrect ) due to signal phase shift if you subscribe and add signall from these 2 antennas it is possible to find quadrant from where signal does come .
You can see such antennas are still used on ships
for navigation for freq range 1 -20 MHz .

More sophisticated using antenna switching techiniques by airport terrestrial navigation departments - this type covers UHF HF freqs.