The dielectric resonator antenna

There is, today, strong interest on the part of both military and commercial users, in antenna systems which can operate efficiently in the millimeter wave region (100–300 GHz) and above. Reducing the size of currently-used microwave frequency antennas to obtain higher resonant frequencies will usually be unsuccessful, either because the small size prohibits economical fabrication or because the inherently larger conduction losses at the higher frequencies result in inefficient operation.