Before revision: Since an array of omnidirectional antennas radiates two beams 180° apart broadside from both sides of the antenna, it often is either mounted in front of a reflector, or is composed of directive antennas such as Yagi or helical antennas, to give a unidirectional beam.
After revision: Since an array of omnidirectional antennas radiates two beams 180° apart broadside from both sides of the antenna, it is usuallyflat either mounted in front of a reflector, or is composed of directive antennas such as Yagi or helical antennas, to give a unidirectional beam.