Measurement Testing

Mjr · Site Admin Joined: 13 Jul 2005 Posts: 294

A question recently arose concerning RF signal amplitude:

What is the effect on the range of RF communication after the signals pass through steel walls? Approximately how much power is need to pass through these steel walls and have the signal travel about 300 feet?

A particular project involves wireless communication between 2 devices, each of which is on opposite sides of an airplane (outside). So the signal essentially has to pass through the plane.

Answer:

Most airplanes are made of aluminum, not steel.

The signal does not have to pass directly through the direct straight line. Diffraction and reflections will occur around the object blocking the Line Of Sight path. This diffraction can be modelled using GTD/UTD (Google those terms) -- but it gets complicated.

If the frequency is sufficiently low, the RF wouldn't even "notice" the "small" object. For example, cell phones work perfectly fine on airplanes as well.