RADIATION PATTERN MEASUREMENT

The patterns of antennas can be measured in transmit or receive mode. Some types of antennas must be measured under both transmit and receive conditions. In general, the
pattern of an antenna is three-dimensional (Figure below).



Because it is not practical to measure a three-dimensional pattern, a number of two-dimensional patterns are measured. A two-dimensional pattern is referred to as a pattern cut. Pattern cuts can be obtained by fixing f and varying q (elevation pattern), or fixing q and varying f (azimuth pattern). To achieve the desired pattern cuts, the mounting structure of the system must have the capability to rotate in various planes. This can be accomplished by using different types of positioners such as Elevation-over- Azimuth (EL/AZ) or Azimuth-over-Elevation (AZ/EL) mounts.