How to the signal strength of an RF signal be measured

distancesignal

I am a graduating ECE student and we are currently making our project study. Our group would like to make a proximity indicator. Initially, we planned to use Radio Frequency for this. The idea was to measure the signal strength of the output signal in terms of voltage. We were to use AD8313 to be able to convert the db output signal to voltage. Unfortunately, our component has not yet arrived and we are forced to look for alternative ways. Could you please suggest other ways on how to accomplish this?

Best Answer

Andy is correct - we really need to know the details about frequency, power out etc. to give a precise answer but as a general solution you will require a pick-up/tuned circuit (LC), a sensitive detector (diode) and some sort of buffer/amplifier (possibly a FET/mosfet/op amp) and a meter to indicate the field strength.

Accurate calibration of what the meter reading actually means is of course a different matter but if you just want to detect a particular field strength for proximity you could always use a comparator to set the point at which the field strength will exceed a certain value of voltage output.

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