How does a log-periodic antenna work?
How does a log-periodic antenna work?
Electrically, it simulates a series of two or three-element Yagi-Uda antennas connected together, each set tuned to a different frequency. LPDA antennas look somewhat similar to Yagi antennas, in that they both consist of dipole rod elements mounted in a line along a support boom, but they work in very different ways.
Why is it called log periodic antenna?
Log periodic antenna is so named because its characteristics, could be gain or impedance, shows a periodic variation with log of the input frequency. The principle of operation may be explained by considering a log periodic dipole array. It contains a large number of elements.
What is the polarization of a log periodic antenna?
Log-periodic dipole antennas (LPDA) are mainly used for the range above 300 MHz and biconical antennas for the range less than 300 MHz. These two antennas have linear polarization.
Why log periodic antenna is frequency independent?
Explanation: Log periodic antenna is frequency independent. The geometrical structure of the antenna changes according to the wavelength. It is also called as Frequency Independent antenna. Its electrical performance is dependent on logarithmic of frequency only.
Which of the following describes a log periodic antenna?
A log periodic antenna is described as one in which the length and spacing of the elements increases logarithmically from one end of the boom to the other. The advantage of this type of antenna arrangement is that it allows operation over a wide range of frequencies, rather than one static frequency band.
What is the approximate gain of log-periodic antenna for the best performance?
between 7 to 12dB
5. What is the approximate gain of LPDA for best performance? Explanation: For best performance of the LPDA antenna, the gain lies between 7 to 12dB. It is a broadband antenna.
What are Yagi-Uda and log-periodic antenna?
Both Log-Periodic Antennas and Yagi antennas are high gain directional antennas. The main difference between these antennas is that Log-Periodic Antennas support wider frequency bandwidths and are physically much larger than Yagi antennas. Conceptually, Log-Periodic Antennas are similar to Yagi Antennas.
Is Yagi-Uda a log-periodic?
They can be thought of as two or three element Yagi antennas connected together, each tuned to a different frequency. This gives Log-periodic antennas the ability to work across a wide range of frequencies, whereas Yagi-Uda antennas are optimized for one particular frequency range.
What does logging mean in biology?
The formal definition of a logarithm is as follows: the base a logarithm of a positive number x is the exponent you get when you write x as a power of a where a > 0 and a ≠ 1. That is, loga x = k if and only if a k = x. The key to taking the logarithm of x > 0 is to rewrite x using base a.
What is the difference between log on and log in?
In nontechnical web parlance, log on often means to visit (especially a website), and log in means to sign in with a username and password. For example, we could say you logged on to this website simply by visiting this page, but you won’t be logging in because nothing on this site requires a username and password.