Why Military Antenna Manufacturers Are Very Important

By Carolyn Hughes


Antennas are electrical devices that will convert an electric power into a radio wave and vice versa. These are often used with radio transmitters or radio receivers. Antennas are the essential components for all the equipment that have radios. These are often used in broadcast television, communication receivers, cell phones, radio broadcasting, two way radio, radar, and satellite communication. It can also be used in some other devices such as wireless microphones, wireless computer networks, RFID tags, garage door openers, Bluetooth devices, baby monitors.

One type for this that is being utilized by militaries is the mono pole. It is consist of a single conductor such as metal rod that is mounted above the ground or artificial surface for a conduction. Umbrella is one of the types of mono pole that is often utilized in a long range military communication. These productions of antennas by the military antenna manufacturers became so much useful to them.

The umbrella is a very large wire that transmits an antenna that is used for a VLF band. It is consist of a mast radiator tower which is attached to the top of multiple wires that are extending from a mast to the ground, just like a tent or an umbrella. And this is also insulated in its ends. It has a narrow bandwidth and may require large loading coils and low resistance of counterpoise ground.

Another type is array and its type that is utilized for military purposes, specifically for radar system and jamming system is the phased array. This is a higher gain antenna utilized for UHF and also for microwave frequencies that is steered electronically. It is consist of several dipoles in two dimensional arrays. Each dipole is fed through electric phase shifters that are being controlled by computer control systems.

Radio kites are the oldest types of antennas. These are utilized to carry radios in aloft, higher compared to practical mast. The kites are usually associated with the portable radio system and also utilized to increase radios range for naval ships. Usage of these have limitations due to difficulties in consistent height maintenance, unpredictable wind, and antenna, transmission, and reception improvements.

Ground is one important thing in the during the installation of these antennas. The height and electrical properties, and as well as the permittivity and conductivity are important. Also, in particular for the antennas in mono pole, the grounds are the return connection of current, and thus, having some effects to it.

For those that have a low frequency to high frequency, the grounds will behave as lossy dialectrics. Thus, these are being characterized by conductivity and permittivity. For lower frequencies, it will act as the good conductor.

If a frequency ranges from 3 up to 30 megahertz, a large proportion of the energy from antennas that are horizontally polarized will reflect. While a vertically polarized one is not reflected except for its grazing incidence. But the reflection of these grazing angles will be in phase with the direct waves.

The net qualities of reflection will be dependent on the surface topography. If there are some irregularities of surfaces that are smaller than wavelength, there is a specular reflection. But if irregularities are not small, the reflections are shifted by the random phases.




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