0A radiation pattern (or field pattern) is a graph that describes the relative far field value, E or H, with direction at a fixed distance from the antenna. A field pattern includes an magnitude pattern | E| or | H| and a phase pattern ∠E or ∠ H.
A power pattern is a graph that describes the relative (average) radiated power density | Pav| of the far-field with direction at a fixed distance from the antenna.
By the reciprocity theorem, the radiation patterns of an antenna in the transmitting mode is same as the those for the antenna in the receiving mode.
A radiation pattern shows only the relative values but not the absolute values of the field or power quantity. Hence the values are usually normalized (i.e., divided) by the maximum value.
