An antenna system for a radio frequency ("RF") wireless keyboard includes a metallic plate as a part of the antenna system. The metallic plate is located within the wireless keyboard. A RF transmitter is coupled to the metallic plate and an antenna wire which form an the antenna loop. The antenna loop...http://www.google.com.tw/patents/US6138050?utm_source=gb-gplus-share專利 US6138050 - Antenna system and apparatus for radio-frequency wireless keyboard
