A radio frequency identification (RFID) device includes a communication arrangement which receives data from and/or sending data to a data processing unit via a wireless communication. In addition, the RFID device includes a solar cell/panel which provides power for the RFID device. ...http://www.google.com.hk/patents/US20070015549?utm_source=gb-gplus-share專利 US20070015549 - Power source system for RF location/identification tags
