# How does antenna relate to wavelength?

## How does antenna relate to wavelength?

The equation clearly shows that the higher the frequency, the shorter the wavelength, and the smaller the antenna. For example, the wavelength for 433.92 MHz is 0.69 m (~2.3 ft.), and the wavelength for 916 MHz is 0.33 m (~1.0 ft.).

## Is a full wavelength antenna better?

It’s length (half of the wavelength) gives you the better performance than other lengths….. It may be gain, efficiency, directivity, return loss, etc….. I think the gain of the half wave dipole is higher than the full wave length antenna.

**Which condition is true for resonant antenna?**

An antenna is said to be resonant if its input impedance is entirely real, i.e. Zin = R + j*0. In this case the voltage and current are in phase at the antenna’s terminals.

### What is the impedance of an antenna?

One definition of antenna impedance is the resistance and reactance seen at the antenna terminals or the ratio of electric to magnetic fields at the input. The primary intent of this paper is real-time compensation for changes in the driving point impedance of an antenna due to frequency deviations.

### What is the impedance of a resonant antenna?

Irrespective of the feedline characteristics (assuming there is a feedline—could be fed directly by equipment), at its feed point, an antenna presents a certain impedance value as a function of frequency. The frequency for which this impedance is resistive (contains no reactive component) is the resonant frequency.

**What is the SWR of a resonant antenna?**

A resonant antenna does not necessarily have a low SWR. Antennas with a feedpoint impedance of 5 + j0 or 500 + j0 are resonant, by this definition, but either will have an SWR of 10 : 1 when fed with 50 ohm cable. And either may still be a useful antenna.

## What is the real impedance of a quarter wavelength?

A resonant quarter wavelength with a dedicated counterpoise or earth system results in a feeding point impedance between 35 and (say) 60 Ohm pure resistive. That is an impedance that can be matched with simple means to most transmitter systems that require 50 Ohm real impedance. Most simple antenna systems are based on quarter wavelength antennas.

## How are nonresonant antennas and resonant antenna alike?

The Non-resonant antennas are like nonresonant transmission lines. Nonresonant transmission lines do not have standing waves. Hence they do not have any reflected waves and they have only forward travelling waves.