An UWB to three sub-bands frequency reconfigurable antipodal Vivaldi antenna

A frequency reconfigurable antipodal Vivaldi antenna is presented. Three strip lines are printed on one wing of the antipodal Vivaldi at different vertical positions to achieve frequency reconfiguration. By using a single switch at each strip, the antenna can be operated either in an ultra-wideband mode or in one of three different sub-bands. A prototype has been simulated and fabricated and a permissible agreement between simulations and measurements can be observed. The proposed approach to achieve frequency reconfiguration on antipodal Vivaldi antennas allows having an UWB mode or a narrower band mode, which can make it a good candidate for compact cognitive radios and wireless applications requiring frequency agility.