distance measurement in RF

[cjac]

Hello All,

I'm trying to implement a transmission system able to compute distance, in the case of one fixed terminal and the other moving.
The moving terminal has to be as simple as possible.
Then if possible without reception feature(only transmission circuit...but I m not sure it s possible...). Then all the complexcity should be placed in the fixed terminal.

What I'm looking exactely is the way to compute the distance between the two systems knowing that only the fixed one has to know this value) the max distance should be +-150m, the precision should be 1-5 m.

The transmission frequency will be around 433MHz.

I nkow there is still lot of abstraction, but I realy don't see with what I have to begin....
in one word...........HEEELP

Thanks a lot to all of you
CJac

 

[nbucska]

Besides legalities ( 433 MHz is not approved for RADAR )
your wavelength is around 25 cm. I think you will have
difficulties to pulse modulate and detect this with 3 ns accuracy. ( Any tuned circuit will ring much longer ) <nbucska@pcperipherals.com>

 

[rafeh1]

Actually you want 2 emitters and one detector on your moving target.

IF they are transmitting the same signal you may be able to compute the phase + clock differneces and have fairly good accuracy