What is Semipassive Tag

We are in the midst of what may become one of the true technological transformations of our time. RFID (radio frequency identification) is by no means a new technology. RFID is fundamentally based on the study of electromagnetic waves and radio, pioneered in the 19th century work of Faraday, Maxwell, and Marconi. The idea of using radio frequencies to reflect waves from objects dates back as far as 1886 to experiments conducted by Hertz. Radar was invented in 1922, and its practical applications date back to World War II, when the British used the IFF (Identify Friend or Foe) system to identify enemy aircraft (Landt, 2001). Stockman (1948) laid out the basic concepts for RFID. However, it would take decades of development before RFID technology would become a reality. Since 2000, significant improvements in functionality, decreases in both size and costs, and agreements on communication standards have combined to make RFID technology viable for commercial and governmental purposes. Today, RFID is positioned as an alternative way to identify objects with the ubiquitous bar code.