C Band Circular and Linear Polarised Signals Explained

To receive signals from a circularly polarised satellite you require a device that converts circular to linear polarisation, this can be achieved through two methods. The first method is by inserting a dielectric plate (see picture below) in to the existing LNBF.

This method is by far the simplest and least cost intrusive method to receive circular polarised satellite signals. However, this method is very inefficient and will reduce your satellite dish’s performance by 3dB or effectively halving the size of the satellite dish you are using.

This may be acceptable if you are using a large antenna but if you are using the minimum size antenna to receive the Australia Network you will need to use the second method to receive circular polarised satellite signals.

The second methods uses a device called a waveguide polariser, this device is installed between the feedring and the LNB on a satellite dish and allows the reception of circular polarised signals. This technique will preserve your satellite signal strength at the current level. This second method, the Waveguide Polariser is the most efficient method to receive circular polarised satellite signals.