I saw a demonstration of an RF detector being brought close to a mobile phone. As the detector was moved away, the number on it dropped to zero. How can that be? Shouldn’t there be some RF signal from the phone all the way to the cell tower, so that the phone can communicate with the tower?

Question

I saw a demonstration of an RF detector being brought close to a mobile phone. As the detector was moved away, the number on it dropped to zero. How can that be? Shouldn’t there be some RF signal from the phone all the way to the cell tower, so that the phone can communicate with the tower?

In: Technology

Answer 1

Electromagnetic radiation decreases at r² rate. So at 3 x distance from the antenna, it is 1/9th of the power, at 10 x the distance from the antenna is is 1/100th of the power.

If the RF detector was set to a range then it would fall out of that range very quickly.