Wideband Frequency-Domain and Space-Domain Pattern Reconfigurable Circular Antenna Array

This paper presents a wideband circular antenna array with a frequency-domain and space-domain reconfigurable radiation pattern. A wideband circular array antenna is designed with omnidirectional radiation pattern, in azimuth direction, throughout the whole frequency band. The antenna array consists of eight TEM horn antennas. The antenna array exhibits an omnidirectional azimuthal radiation pattern when all eight ports are excited with signals of the same magnitude and phase. The antenna array is fed through eight reconfigurable bandstop filters and a power splitter. This enables it to provide an omnidirectional azimuthal pattern along with a single directional pattern null in a given spatial direction and at a certain frequency. Both the spatial direction and the frequency can be altered. The antenna works from 0.8 to 3 GHz. The antenna array will be useful in combating interference in wideband communication systems. It will also be of value in surveillance military applications.