ABSTRACT
In Chapter 7, the UWB antennas with tunable band-notched characteristics are investigated and discussed. The realization of single/dual/triple notched-band functions using different techniques such as etching of slots in the radiating patch and ground plane or adding parasitic elements or stubs near the radiator has already been discussed in previous chapters. The above mentioned techniques are used not only for obtaining band-notched characteristics but also for removing the requirements of additional bandstop filters. But unfortunately, these band-notched UWB antennas fail to reject unwanted interference completely. In order to reduce the interference completely, UWB notched-band antennas with tunability features are required. The tuning is performed using the micro electromechanical switches (MEMS), PIN diodes, stepper motors, shorting circuits, and optically controlled switches.
