To get an easy answer you have to add a radio trigger to trigger the transmitter and all the receivers at the same time. Each distance specifies a sphere and where the spheres all intersect you will find the transmitter.
Without a simultaneous trigger you will only have the differential time of arrival to go by. That will tell you that the distance to the first receiver is 'n' cm shorter than the distance to the second receiver. I think that defines some kind of hyperbolic plane. Each pair of hyperbolic planes will intersect at some curved line in space. Enough planes (3?) and you find where the curved lines intersect.
If you do not use a simultaneous trigger and you work out the shortest distance in cm to get your position just note your receivers need to be +- 30cm apart from each other to get a good differential reading between all the receivers .
Now I just need to figure out how to determine the distance if the transmitter is always on...
How long have you got?
Instead what I think I need to do is make a circuit that can pulse the transmitter on/off at a certain interval that I can control. Maybe I'll be better off getting an adruino micro and programming that to pulse at a certain interval. But I believe this can be done with a circuit. Do you have any ideas?
Does anyone have any ideas on how I can measure the distance of the transmitter to the receiver?- Transmitter will have a fixed starting position x cm away from the receiver. x will be known- The transmitter will be always on at 40Khz when it is moving, however thinking about it I may need to have it pulse - am I correct in thinking this? if so how should I go about achieving this?