Distance between transmitter and receiver detection
I know the formula for calculating the distance
My question is hardware
With the circuit and how can it work ?
EM and sound are very different
There is no exact distance. TX power level, receiver gain, antenna gains, path losses and several other things all contribute to path distance
tell a lot more about what you are trying to do and maybe then people can offer specific advice
cheers
Dave
In any radio link, distance between the antennas causes the propagation loss. This loss is proportional to the distance but the wavelength, presence of ground and the size of antennas affects the proportionality.
The function of propagation loss vers.distance is not exactly"linear".
Make an experiment to see for yourself.
Selecting hardware is distance depending. You can use a car odometer to measure distance to your job from home, but is not a good tool for measuring distance between two atoms or two planets.
Same problem when using radios, needed equipment is depending on environment, distance, need of precision......
Measuring distance with aid of EM radio is normally measuring time delay in some form.
As speed of EM waves can be assumed to be c in free space do we get the formula: d=t•c where d=distance t=time c=speed of light.
By selecting distance range you already know your input timing parameter expected range. In combination with knowing need of precision can at least some hardwares be excluded as less usable.
Send a signal to planet Mars and it is enough to use a stopwatch to measure how long it takes for the echo to return. From that can distance be estimated within less then a few percent error.
For short distances can it be hard to use a manual stopwatch. An electronic time counter is better. For short distances and high precision must time counter be fast and precise. Complex systems may also need complex time synchronization between TX and RX units.
Finding distance to the end of a cable, for that can some kind of reflectometer used. It sends a short pulse and from time when echo is received can distance to cable end be calculated.
GPS and RF radar systems are based on similar ideas.
Also related to time is measuring phase delay. A lot of distance measuring systems are based on this. Advantage is that it require less precise clocks.
Decca navigation is an example.
For known path loss at a certain distance between a TX an a RX unit, can other distances be calculated by measuring received signal level. It is a unreliable method in environments where reflection or shadowing can occur. Free space is better.
Somewhat better in an disturbed environment is to do triangulation between three receivers at different locations. Received signal can then be a parameter for both distance and location estimation of an transmitter.
Using even more receivers can improve result and that is used for example when deciding location of discharges in the atmosphere (lightning is a kind of EM transmitter). See more here.
No idea. You have not provided any information about your formula, what method it is based on, distance range or needed precision.