What is parasitic element in Yagi-Uda antenna?

The parasitic elements in a Yagi antenna are mounted parallel to the driven element, with all the elements usually in a line perpendicular to the direction of radiation of the antenna. What effect a parasitic element has on the radiation pattern depends both on its separation from the next element, and on its length.

What are parasitic elements in antennas?

A parasitic element is an element, which depends on other’s feed. It does not have its own feed. Hence, in this type of arrays we employ such elements, which help in increasing the radiation indirectly. These parasitic elements are not directly connected to the feed.

Is Yagi-Uda an array antenna?

A Yagi–Uda antenna or simply Yagi antenna, is a directional antenna consisting of two or more parallel resonant antenna elements in an end-fire array; these elements are most often metal rods acting as half-wave dipoles.

What is a parasitic array?

A parasitic array consists of a single driven element connected to the feedline, and other elements which are not, called parasitic elements. It is usually another name for a Yagi-Uda antenna.

What do you mean by parasitic elements?

In electrical networks, a parasitic element is a circuit element (resistance, inductance or capacitance) that is possessed by an electrical component but which it is not desirable for it to have for its intended purpose.

How many parasitic elements are used in a driven array?

5 parasitic elements
A Yagi antenna with one driven element (A) called a folded dipole, and 5 parasitic elements (B and C). A feed line leading to the receiver (not shown)) is attached to the driven element at D.

How do you increase the gain of a Yagi-Uda antenna?

In the designs of yagi-uda antennas, directors play a key role in achieving better gain and directivity. Usually, their length is 5% smaller than the active element i.e. lies between 0.4λ to 0.45λ. Generally, gain is enhanced by adding number of directors as well as by optimizing the spacing between them.

What are the three elements of Yagi-Uda antenna?

There are three types of element within a Yagi antenna:

• Driven element: The driven element is the Yagi antenna element to which power is applied.
• Reflector: The reflector element is made to be about 5% longer than the driven element.
• Director: The director or directors are made to be shorter than the driven element.

What is the advantage of adding parasitic elements to a Yagi array?

In general, the greater number of parasitic elements used, the greater the gain. However, a greater number of such elements causes the array to have a narrower frequency response as well as a narrower beamwidth. Therefore, proper adjustment of the antenna is critical.