RF is short for radio frequency. RF is any frequency within the electromagnetic spectrum associated with radio wave propagation. When an RF current is supplied to an antenna, an electromagnetic field is created that then is able to propagate through space. Many wireless technologies are based on RF field propagation. These frequencies make up part of the electromagnetic radiation spectrum.
Electromagnetic radiation consists of waves of electric and magnetic energy moving together (that is, radiating) through space at the speed of light. Taken together, all forms of electromagnetic energy are referred to as the electromagnetic spectrum. Radio waves and microwaves emitted by transmitting antennas are one form of electromagnetic energy. Often the term electromagnetic field or radiofrequency (RF) field may be used to indicate the presence of electromagnetic or RF energy.
An RF field has both an electric and a magnetic component (electric field and magnetic field), and it is often convenient to express the intensity of the RF environment at a given location in terms of units specific for each component. For example, the unit "volts per meter" (V/m) is used to measure the strength of the electric field and the unit "amperes per meter" (A/m) is used to express the strength of the magnetic field.
RF waves can be characterized by a wavelength and a frequency. The wavelength is the distance covered by one complete cycle of the electromagnetic wave, while the frequency is the number of electromagnetic waves passing a given point per unit of time. The frequency of an RF signal is usually expressed in terms of a unit called the hertz (Hz). One Hz equals one cycle per second. One megahertz (MHz) equals one million cycles per second. Different forms of electromagnetic energy are categorized by their wavelengths and frequencies. The RF part of the electromagnetic spectrum is generally defined as that part of the spectrum where electromagnetic waves have frequencies in the range of about 3 kilohertz (3 kHz) to 300 gigahertz (300 GHz).
Probably the most important use for RF energy is in providing telecommunications services. Radio and television broadcasting, cellular telephones, radio communications for police and fire departments, amateur radio, microwave point-to-point links, and satellite communications are just a few of the many telecommunications applications. There are also many non-communication applications that use RF energy. Microwave ovens are a good example of a non-communication use of RF energy. Other important non-communication uses of RF energy are radar and for industrial heating and sealing. Radar is a valuable tool used in many applications from traffic enforcement to air traffic control and military applications. Industrial heaters and sealers generate RF radiation that rapidly heats the material being processed in the same way that a microwave oven cooks food. These devices have many uses in industry, including molding plastic materials, gluing wood products, sealing items such as shoes and pocketbooks, and processing food products. Other industrial applications include testing of RF components and measuring material density.
RF energy is also used in medical applications. It is used in medical treatments such as cosmetic treatments that tighten skin, reduce fat or promote healing. MRI, magnetic resonance imaging, uses RF waves to generate images of the human body. RF is also used to destroy cancer cells.
Because of the multitude of RF applications in the world, it is imperative that products and systems be able to operate in their electromagnetic environment and must not introduce intolerable electromagnetic disturbances back into the environment. Therefore, before a product or system hits the marketplace, it must be tested for RF immunity and emissions. For RF immunity testing, the equipment is exposed to RF disturbances and fields with field strengths and frequency ranges representative of their in-operation environment. On the other hand, when a piece of equipment is tested for RF emissions, the equipment, under normal operation, is monitored for RF disturbances and fields.
To be able to generate the electric fields necessary for RF immunity testing, AR has amplifiers and antennas that cover frequencies from DC to 50 GHz and power from 1 watt to 16,000 watts depending on the frequency. In the 50 years of its existence, AR has provided its’ customers with the highest quality EMC Test products such as amplifiers in addition to superior engineering support experience in the area of EMC Test. 50 years of practical experience translates into a vast knowledge base to draw from. This knowledge allows AR engineers to assist customers in areas of: planning, specifying, problem-solving, in order to put in place an EMC Test system that meets and exceeds expectations. That experience linked with product knowledge has allowed AR to become a premier supplier of EMC Test systems, as well as EMC Test products.