This is important when looking at antennas because they are sensitive to polarisation, and generally only receive or transmit a signal with a particular polarization.įor most antennas it is very easy to determine the polarization. Antenna polarisation basicsįor the electromagnetic wave the polarization is effectively the plane in which the electric wave vibrates. Nevertheless, the polarisation of the antenna is still important. That said, many wireless and mobile phone systems may rely on the fact that there are likely to be many reflections between the transmitter and the receiver and these will tend to mean that a signal will have a particular polarisation when it reaches the receiver. Radio antennas with a particular polarisation will not be effective receiving electromagnetic wave signals with a different polarisation. When designing an antenna, deciding on a particular form of antenna, it is important to understand which way it needs to be polarised. Some antennas are vertically polarised, others horizontal, and yet other antenna types have different forms of polarisation. Antenna Polarization Radio antennas are sensitive to the polarisation of electromagnetic wave and this is an important aspect of their operation.īasic antenna theory Polarisation Resonance & bandwidth Gain & directivity Feed impedanceĪntenna polarisation is an important factor when designing and erecting radio antennas or even incorporating them into small wireless or mobile communications systems.