Monday, July 2, 2007

The Properties of Radio Waves: The Simple Definition.

There are few properties of radio waves which make it distinct and usable. The first consideration is frequency. The frequency of the wave is the number of the cycles of a sine wave completed in one second. In the case of moving waves, such as radio waves, the frequency can be thought as the number of cycles of the wave that pass a given point in one second. The term hertz was designated for use in lieu of the term cycles per second when referring to the frequency of radio waves. Hertz refer to the number of occurrences that take place in one second. The frequencies falling between three kilohertz to three hundred gigahertz are called radio frequencies since they are commonly used in radio communications.
Radio frequencies spectrum is divided into eight frequency bands namely Very low frequency, Low frequency, Medium frequency, High frequency, Very high frequency, Ultra high frequency, Super high frequency and Extreme high frequency. Each of these frequencies is ten times higher in frequency as the one immediately below it.
The second consideration is Harmonics. Any frequency that is a whole number multiple of a basic frequency is known as a harmonic of that basic frequency. The basic frequency itself is called the first harmonic of more commonly the fundamental frequency. Radio operators sometimes encounter signals being radiated simultaneously on both the fundamental frequency and one of its harmonics.
Next is the period of the radio waves. The period of a radio wave is the amount of time required for the completion of one full cycle of its frequency. Also the wavelength has to be considered. The wavelength is the space occupied by one full cycle of a radio wave at any given instant. If for example a radio wave could be frozen in place and measured, its wavelength would be the distance from any one point on a cycle to the corresponding point on the next cycle.
Velocity of a radio wave that is radiated into space by a transmitting antenna is simply that speed at which the wave travels. Radio waves travel in free space at about speed of light and the waves traveling inside earth's atmosphere have lesser speed due to barometric pressure, humidity, molecular content and so on. The frequency of radio wave has nothing to do with the wave velocity.
The radio wave radiated into space by transmitting antenna is a very complex form of energy containing both electric and magnetic fields, hence the term electromagnetic radiations. Both of these fields are perpendicular to each other.
Polarization of radio wave front is an important consideration if the efficient transmission and reception of radio signals. The polarization of a radio wave is determined by the direction of the electric field of the wave with respect to earth. Tymon Hytem has worked in the electronics feild for the past 15 years. He enjoys helping people decide on electronic gadgets from telephones to XM Radio and choosing the perfect XM Satellite Radio system for their needs.

Article Source: http://www.articlepros.com

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