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This tutorial is meant to provide the readers a detailed description of the antennas used in communication systems. After completing this tutorial, you will be able to calculate the parameters of an antenna and decide […]

A person, who needs to convey a thought, an idea or a doubt, can do so by voice communication. The following illustration shows two individuals communicating with each other. Here, communication takes place through sound waves. However, […]

Radiation is the term used to represent the emission or reception of wave front at the antenna, specifying its strength. In any illustration, the sketch drawn to represent the radiation of an antenna is its radiation […]

Radiation intensity of an antenna is closely related to the direction of the beam focused and the efficiency of the beam towards that direction. In this chapter, let us have a look at the terms […]

After the antenna parameters discussed in the previous chapter, another important topic of consideration is the near field and the far field regions of the antenna. The radiation intensity when measured nearer to the antenna, […]

In this chapter, we shall discuss about another important factor in the radiation pattern of an antenna, known as beam width. In the radiation pattern of an antenna, the main lobe is the main beam of […]

In the previous chapter, we have gone through the radiation pattern. To have a better analysis regarding the radiation of an antenna, a referential point is necessary. The radiation of an isotropic antenna, fills this […]

This chapter deals with the parameters of radiated beam of the antenna. These parameters help us to know about the beam specifications. Beam Area According to the standard definition, “Beam area is the solid angle […]

Antennas have to be classified to understand their physical structure and functionality more clearly. There are many types of antennas depending upon the applications applications. Type of antenna Examples Applications Wire Antennas Dipole antenna, Monopole […]

An antenna can be used as both transmitting antenna and receiving antenna. While using so, we may come across a question whether the properties of the antenna might change as its operating mode is changed. […]

A folded dipole is an antenna, with two conductors connected on both sides, and folded to form a cylindrical closed shape, to which feed is given at the center. The length of the dipole is […]

Antennas radiate Electromagnetic energy to transmit or to receive information. Therefore, the terms Energy and Power are associated with these electromagnetic waves and we have to discuss them. An electromagnetic wave has both electric and magnetic fields. Consider the […]

Wire antennas are the basic types of antennas. These are well known and widely used antennas. To have a better idea of these wire antennas, first let us have a look at the transmission lines. […]

The dipole antenna is cut and bent for effective radiation. The length of the total wire, which is being used as a dipole, equals half of the wavelength (i.e., l = λ/2). Such an antenna […]

We have gone through different types of short wire antennas. Now, lets us look at the long wire antennas. The long wire antennas are formed by using a number of dipoles. The length of the wire in […]

If the length of the dipole, i.e. the total wire, equals the full wavelength λ, then it is called as full wave dipole. If a full wavelength dipole is used either for transmission or for reception, let […]

A short dipole is a simple wire antenna. One end of it is open-circuited and the other end is fed with AC source. This dipole got its name because of its length. Frequency range The range of […]

The Rhombic Antenna is an equilateral parallelogram shaped antenna. Generally, it has two opposite acute angles. The tilt angle, θ is approximately equal to 90° minus the angle of major lobe. Rhombic antenna works under the principle […]

A better version of long-wire antennas is the V-Antenna. This antenna is formed by arranging the long wire in a V-shaped pattern. The end wires are called as legs. This antenna is a bi-directional resonant antenna. […]

In the previous chapter, we have studied V-antenna. Its operating frequency is limited. This can be modified by using another antenna, which is a non-resonant antenna or a travelling wave antenna. A travelling wave antenna […]

An Antenna with an aperture at the end can be termed as an Aperture antenna. Waveguide is an example of aperture antenna. The edge of a transmission line when terminated with an opening, radiates energy. This […]

Helical antenna is an example of wire antenna and itself forms the shape of a helix. This is a broadband VHF and UHF antenna. Frequency Range The frequency range of operation of helical antenna is around 30MHz […]

An Antenna with an aperture at the end can be termed as an Aperture antenna. Waveguide is an example of aperture antenna. The edge of a transmission line when terminated with an opening, radiates energy. This […]

Micro strip antennas are low-profile antennas. A metal patch mounted at a ground level with a di-electric material in-between constitutes a Micro strip or Patch Antenna. These are very low size antennas having low radiation. Frequency Range The […]

Slot Antenna is an example of Aperture antenna. A rectangular slot is made on the conducting sheet. These slot antennas can be formed by simply making a cut on the surface, where they are mounted on. […]

To improve the radiation efficiency and directivity of the beam, the wave guide should be provided with an extended aperture to make the abrupt discontinuity of the wave into a gradual transformation. So that all […]

The antennas, which we have discussed till now, used the plane surface. The lens antennas use the curved surface for both transmission and reception. Lens antennas are made up of glass, where the converging and […]

Parabolic Reflectors are Microwave antennas. For better understanding of these antennas, the concept of parabolic reflector has to be discussed. Frequency Range The frequency range used for the application of Parabolic reflector antennas is above 1MHz. These […]

A Collinear array consists of two or more half-wave dipoles, which are placed end to end. These antennas are placed on a common line or axis, being parallel or collinear. The maximum radiation in these arrays is […]

The physical arrangement of end-fire array is same as that of the broad side array. The magnitude of currents in each element is same, but there is a phase difference between these currents. This induction of energy […]

The physical arrangement of end-fire array is same as that of the broad side array. The magnitude of currents in each element is same, but there is a phase difference between these currents. This induction of energy […]

The antenna arrays as seen above, are used for the improvement of gain and directivity. A parasitic element is an element, which depends on other’s feed. It does not have its own feed. Hence, in this type […]

The Yagi-Uda antenna is mostly used for domestic purpose. However, for commercial purpose and to tune over a range of frequencies, we need to have another antenna known as the Log-periodic antenna. A Log-periodic antenna is […]