An antenna device includes a ground conductor plate, and a radiating conductor plate made of a metal plate, which is spaced from the ground conductor plate. The radiating conductor plate is provided with adjusting means for adjusting the electrical length. Thus, the correction of the electrical lengths...http://www.google.com.au/patents/US6972720?utm_source=gb-gplus-sharePatent US6972720 - Antenna device capable of adjusting frequency
