Is log periodic antenna frequency dependent?

Log periodic antenna is frequency dependent. 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.

Why is a log periodic antenna known as frequency independent antenna?

It is basically called a frequency-independent antenna because the impedance of the antenna is not depend directly on frequency but depend upon the logarithmic of frequency. So, this Log Periodic Antenna is also called as “Frequency Independent Antenna”.

What are characteristics of log periodic antenna?

Being log-periodic, the antenna’s main characteristics (radiation pattern, gain, driving point impedance) are almost constant over its entire frequency range, with the match to a 300 Ω feed line achieving a standing wave ratio of better than 2:1 over that range.

Which of the given antenna is frequency independent?

Examples of frequency-independent antennas are log-periodic antennas and spiral antennas.

What is the frequency range of a log periodic antenna?

The frequency range, in which the log-periodic antennas operate is around 30 MHz to 3GHz which belong to the VHF and UHF bands. The construction and operation of a log-periodic antenna is similar to that of a Yagi-Uda antenna.

How is a log periodic antenna similar to Yagi-Uda?

The construction and operation of a log-periodic antenna is similar to that of a Yagi-Uda antenna. The main advantage of this antenna is that it exhibits constant characteristics over a desired frequency range of operation. It has the same radiation resistance and therefore the same SWR.

What are the advantages of a periodic antenna?

The main advantage of this antenna is that it exhibits constant characteristics over a desired frequency range of operation. It has the same radiation resistance and therefore the same SWR. The gain and front-to-back ratio are also the same.

How can a frequency independent antenna be made?

Another way of achieving a frequency-independent antenna is to design an active region that moves not continuously as in the case of the spiral, but in a discrete fashion. The antenna must now have a performance that is repetitive over a number of suitably related frequency subbands, and this, of course, is the log-periodic antenna discussed next.