4. Association of antenna networks

Microwaves are mainly used in applications requiring good directivity (telecommunications, radar, radio astronomy). To achieve this, there are two main methods: reflector antennas and array antennas. In fact, the gain of antennas such as dipoles or printed antennas is quite low, as their radiation is not very directional. Their combination creates an array whose particularity is to have a higher gain in a preferred direction, since the overall electrical size of the antenna is increased. In the case of a directional antenna, radiation patterns have a maximum which is called the main lobe. The other extrema are called side lobes. The angular width of the main lobe is generally defined for an attenuation of – 3 dB. The importance of the secondary lobes is measured by the difference in dB between the level of the main lobe and that of the highest secondary lobe