Download Citation on ResearchGate | On Nov 30, , Juan Carlos Gómez and others published Diseño de Antenas Yagi Uda Usando. Abstract— This paper presents a simple broad band printed Yagi Uda antenna IndexTerms—Printed YagiUda antenna, Reflectors, Directors, Driven element. Yagi-Udaantenna From Wikipedia, the free encyclopedia Drawing of Yagi-Uda VHF television antenna from , used for analog channels.

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Online Calculator Yagi Uda Antenna based on DL6WU

Therefore, the forward waves add together, constructive interference enhancing the power in that direction, while the backward waves partially cancel each other destructive interferencethereby reducing the power emitted in that direction.

A full qntenas of such a system requires computing the mutual impedances between the dipole elements [11] which implicitly takes into account the propagation delay due to the finite spacing between elements.

Commons category link is on Wikidata. In the next section, we’ll explain the principles of the Yagi-Uda antenna.

Yagi–Uda antenna – Wikipedia

Institute of Electrical Engineers of Japan: Yagi antenna design is done most often via measurements, and sometimes computer simulations. John Wiley and Sons. Just considering two such elements we can write the voltage at each feedpoint in terms of the currents using the mutual impedances Z ij:.

The addition of these waves bottom is increased in the forward direction, but leads to cancellation in the reverse direction. These waves combine to produce the net forward wave bottom, right with an amplitude slightly larger than the individual waves.


The work was originally done by Shintaro Uda, but published in Japanese. Yagi Antennas Design Parameters. It is simple to construct and has a high gaintypically greater than 10 dB.

An example of a Yagi-Uda antenna is shown below. Yagi—Uda antennas used for amateur radio are sometimes designed to operate yagi-ua multiple bands.

Using a second set of traps, a “triband” antenna can be resonant at three different bands.

This has been computed for two exact half-wave dipole elements at various spacings in the accompanying graph. In other projects Wikimedia Commons. Yagi demonstrated a proof of conceptbut the engineering problems proved to be more onerous than conventional systems. The director elements those to the right of yag-iuda feed in Figure 1 will be shorter than resonant, making them capacitive, so that the current leads the voltage.

The solution of the system then is as follows. In the next section on Yagis, I’ll go further into the design of Yagi-Uda antennas. Retrieved 18 September Wikimedia Commons has media related to Yagi-Uda antennas.

Let the driven element yagiu-da designated 1 so that V 1 and I 1 are the voltage and current supplied by the transmitter. Radio frequency antenna types Antennas radio Radio electronics Japanese inventions Amateur radio.

Yagi Antennas Design Parameters Top: This so-called trap has the effect of truncating the element at the higher frequency band, making it antsnas a half wavelength in length.

Yagi–Uda antenna

TV antennas are still a major application of the Yagi antenna. However the “Yagi” name has become more familiar with the name of Uda often omitted.

A picture of Professor Yagi with a Yagi-Uda antenna is shown below. Geometry of Yagi-Uda antenna. The element to the left of the feed element in Figure 1 is the reflector. From Wikipedia, the free encyclopedia. The Yagi was first widely used during World War II for airborne radar sets, because of its simplicity and directionality.


Retrieved 29 July One way of thinking about the operation of such an antenna is to consider a parasitic element to be a normal dipole element of finite diameter fed at its centre, with a short circuit across its feed point. By using this site, you agree to the Terms of Use and Privacy Policy. This element is important in determining the front-to-back ratio of the antenna. We can also solve for the voltage V 1 at the feedpoint of the driven element using the earlier equation:.

The combination of the director’s position and shorter length has thus obtained a unidirectional rather than the bidirectional response of the driven half-wave dipole element alone.

How the antenna works. In fact, that would be the case were we to construct a phased array with rather closely spaced elements all driven by voltages in phase, as we posited. While the above qualitative explanation is useful for understanding how parasitic elements can enhance the driven elements’ radiation in one direction at the expense yai-uda the other, the assumptions used are quite inaccurate.

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