Yagi Uda Antenna
Yagi-Uda or Yagi antenna is a high gain antenna and it is known as after the name of Professor S. Uda & H. Yagi. Yagi antenna was invented and described in Japanese by the former sometime around 1928 by Professor S. Uda and afterward, it was translated or described by H. Yagi in English.
Components of Yagi Antenna
Yagi antenna has one driven element for inserting feed, one reflector for reflecting signals, and one or more directors. So, the yagi uda antenna is an array of one driven element (or active elements where the power from the transmitter is fed or which feeds received power to the receiver) and one or more parasitic elements (which are not connected directly to the transmission line but electrically coupled).
The driven element is a resonant half-wave dipole generally of the metallic rod at the frequency of operation or resonance frequency. The parasitic elements are made my metal in rod shape and they are arranged in one axis, parallel with the driven element and at the same line of sight level. The parasitic elements receive their excitation from the voltages induced in them by the current flow in the driven elements.
