LowPowerLab Forum

Hardware support => RF - Range - Antennas - RFM69 library => Topic started by: gussabina on August 20, 2016, 12:20:49 PM

Title: Antenna requirements
Post by: gussabina on August 20, 2016, 12:20:49 PM

Hi:

Does the antenna have to be a straight wire? Could it be a flexible wire?
Any particular minimum diameter?

Thanks
Gus

Title: Re: Antenna requirements
Post by: Felix on August 20, 2016, 05:22:06 PM

I suggest searching the forum for the term "antenna".
Also reading this article (https://en.wikipedia.org/wiki/Antenna_(radio)) is a good primer. Many other good articles online about antennas.
The tldr is the happier the antenna the better signal propagation. Different types of antennas behave differently. The wire monopole is an omnidirectional antenna and should ideally be perpendicular to a GND plane equal in radius to the antenna length (quarterwave). Similar for a dipole but usually the GND is opposite to the antenna. There are helical antennas and yagis and all kinds. Keep the antenna as straight as you can afford in your application or the signal will start to drop significantly if you mangle it.