parasitic array การใช้

Driven arrays, in which all the radiating elements are connected to the energy source, have smaller losses than parasitic arrays.
Also called a " beam antenna ", or " parasitic array ", the Yagi is very widely used as a high-gain antenna on the bandwidth of a Yagi antenna, the frequency range over which it has high gain, is narrow, a few percent of the center frequency, and decreases with increasing gain, so it is often used in fixed-frequency applications.