# Why do we not use both E and B fields for a receiving antenna?

An antenna is an electrical device which converts electric power into radio waves and vice versa we all know this.

In transmission, a radio transmitter supplies an electric current oscillating at radio frequency (i.e. a high frequency alternating current (AC)) to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic waves (radio waves). The electromagnetic wave has an E and B field which are perpendicular to each other; but in antenna reception we only use the E field of an electromagnetic wave in order to produce a tiny voltage at its terminals, that is applied to a receiver to be amplified.

Why do we not use both E and B fields for reception? Can we produce more voltage by using both E and B fields?

• Antennas that use the E field are almost always a very different design than antennas (usually Loop antennas) that use the B field. Therefore, designing an antenna for both E field and B field is at cross purposes as your design will either favor E field or the B field. But, antennas that are designed for the E field only, or B field only are common and in use. Aug 18, 2015 at 16:05
• On your last question about producing more voltage. The voltage produced by the E-field and B-field do not add to create higher voltage levels. They are out of phase with each other. You use one or the other but using both is definitely not typical. Aug 18, 2015 at 17:12
• @K7PEH: They are actually in phase only in the near field they are out of phase (90°). But later because of the maxwell equations they get in phase (stable state) Aug 18, 2015 at 19:43
• IIRC there is a special type of antenna called the helical wire antenna which is basically a monopole antenna with a helical shape to it. In theory it kinda looks like it can catch both b and e fields being that it is a helical (solenoid) shape and when straightened out is basically a monopole antenna. I know anecdotally it can work for 2.4ghz because I built an antenna for wifi back in the day. IDK if that helps the context at all. Mar 19, 2023 at 5:19