The Yagi antenna or Yagi-Uda antenna or aerial is a particularly popular form of antenna where directivity and gain are required. Although the Yagi has become. The famous yagi-uda antenna is discussed. The background on yagis (the yagi antenna) are given starting with a discussion of the Japanese inventor Yagi. This example optimizes a 6-element Yagi-Uda antenna for both directivity and input match using a global optimization technique.

Author: Tojagrel Targ
Country: Namibia
Language: English (Spanish)
Genre: Business
Published (Last): 20 April 2009
Pages: 289
PDF File Size: 7.47 Mb
ePub File Size: 5.30 Mb
ISBN: 177-5-37517-212-1
Downloads: 66593
Price: Free* [*Free Regsitration Required]
Uploader: Mushicage

The input reflection coefficient for the optimized Yagi-Uda udz is computed and plotted relative to the reference impedance of. These names identify the positions relative to the driven element.

Each element is of length Diand separated from the adjacent director by a length SDi. For studying various parameters of Yagi – Uda antenna, a transmitter of frequency MHz is designed. Desenvolvimento de Antena para Telefonia Celular Abstract- In this article, we have proposed a novel Yagi antenna that has both compactness of resonant antenna and broadband characteristics of The director elements those to the right of the feed in Figure 1 will be shorter than resonant, making them capacitive, so that the current leads the voltage.

The feed antenna is almost always the second from the end, as shown in Figure 1. Retrieved from ” https: Typically each director will add around 1 dB of gain in the forward direction, although this level reduces as the number of directors increases. However, Yagi always acknowledged Uda’s principal contribution to the design, and the proper name for the antenna is, as above, the Yagi—Uda antenna or array.

Yagi antenna advantages The Yagi antenna offers many advantages over other types of antenna in many applications, yet both advantages and disadvantages need to be weighed up to ensure the correct type of antenna is chosen for any particular use.: The element to the left of the feed element in Figure 1 is the reflector.


However using the above kinds of iterative analysis one can calculate the performance of a given a set of parameters and adjust them to optimize the gain perhaps subject to some constraints. Plug and Play Integration. This has been computed for two exact half-wave dipole elements at various spacings in the accompanying graph.

Yagi—Uda antennas used for amateur radio are sometimes designed to operate on multiple bands.

The back lobe is small resulting in a good front to back ratio for this antenna. How the antenna works. The above graph shows that the gain is increased by about 2. Yagi – Uda Antenna is a widely used roof top DVB-T2 receiver antenna due to its high forward gain capability, low cost and antean in construction.

This would tend to cancel the radiation of the driven element. Abstract— This paper presents a simple broad band printed Yagi Uda antenna operating at a resonant frequency of MHz Consider a Yagi—Uda consisting of a reflector, driven element and a single director as shown here.

This is machine translation Translated by. Yagi Antennas Design Parameters Top: Accordingly it was Hidetsugu Yagi who wrote papers in English. Typically, the first director will add approximately 3 dB of overall anetna if designed wellthe second will add about 2 dB, the third about 1.

Yagi Antenna / Yagi-Uda Aerial

Retrieved 4 July The optimized Yagi-Uda antenna achieves a forward directivity greater than 10 dBi, which translates to a angena greater than 8 antrna relative to a dipole. The waves from the multiple elements superpose and interfere to enhance radiation in a single direction, achieving a very substantial increase in the antenna’s gain compared to a simple dipole. Retrieved 15 April The amplitude and phase of the current that is induced in the parasitic elements is dependent upon their length and the spacing between them and the dipole or driven element.

The design for the Yagi antenna appears to have been initially developed not by Yagi who was a student, but his Professor Shintaro Uda. This is very better Institute of Electrical Engineers of Japan: Yagi antenna radiation pattern The antenna can be optimised to either reduce radiation in the reverse direction by altering the length and spacing of the reflector or it can be optimised to produce the maximum level of forward gain.


Yagi–Uda antenna – Wikipedia

Array Antenna, polarization, radiation pattern, stacking distance, UHF antenna, When questioned, the technician said it was an antenna named after a Japanese professor. Indeed, the latter had so many antenna elements arranged on its back — in addition to its formidable turreted defensive armament in the nose and tail, and atop the hull — it was nicknamed the fliegendes Stachelschweinor “Flying Porcupine” by German airmen.

It is apparent that Yagi did not aim to steal the publicity at all and as a result the design now bears the names of both men and is formally known as the Yagi-Uda antenna. Based on your location, we recommend that you select: Very complicated Yagi designs were developed to give adequate gain over the broad television bands.

The rest of the elements are parasitic – they reflect or help to transmit the energy in a anteha direction. The wave green from the driven element excites a current in the passive director which reradiates a wave blue having a particular phase shift see explanation in text.

These choices are an initial guess and will serve as a start point for the optimization procedure. Consequently, these antennas are often empirical designs using an element of trial and erroroften starting with an existing design modified according to one’s hunch. The radiating element consists of a Yagi -like antenna fed by a microstrip That is, they reradiate power which they receive from the driven element they also interact with each other.

All Examples Functions Apps. Retrieved 29 July However all the original papers were all in Japanese and accordingly the design was not publicised outside Japan.