Introduction to RF testing

RF is an abbreviation for radio frequency.RFIs any frequency in the electromagnetic spectrum related to the propagation of radio waves. When radio frequency current is supplied to the antenna, an electromagnetic field is generated, which can then propagate or propagate in space. Many wireless technologies are based on RF field propagation. These frequencies form part of the electromagnetic radiation spectrum.

Electromagnetic radiation consists of waves of electrical energy and magnetic energy, which move together in space at the speed of light (that is, radiation). In summary, all forms of electromagnetic energy are called electromagnetic spectrum. Radio waves and microwaves emitted by transmitting antennas are a form of electromagnetic energy. The term electromagnetic field or radio frequency (RF) field is usually used to refer to the presence of electromagnetic or RF energy.

The RF field has both electrical and magnetic components (electric and magnetic fields). Generally, it is convenient to express the intensity of the RF environment at a given location in units specific to each component. For example, the unit “volts per meter” (V/m) is used to measure the electric field strength, and the unit “amperes per meter” (A/m) is used to represent the magnetic field strength.

Wavelength and frequency can characterize RF waves. The wavelength is the distance covered by a complete electromagnetic wave cycle. At the same time, frequency is the number of electromagnetic waves passing through a given point per unit of time. The frequency of an RF signal is usually expressed in units called hertz (Hz). 1 Hz is equal to one cycle per second. One megahertz (MHz) is equal to one million cycles per second, while one gigahertz (GHz) is equal to one billion cycles per second, that is, one gigahertz.

RF test application

From telecommunications to non-communication applications and medical purposes, RF energy is integrated in a variety of applications. Telecommunications is probably the most common and widely used form of this energy source. We can find it in radio and television broadcasting, radio communications of police and fire departments, amateur radio, microwave point-to-point links, cellular equipment, and satellite communications. In more specific applications, such as in the medical field, RF energy has the same specified purpose. MRI (magnetic resonance imaging) uses RF waves to generate images of the human body. Radio frequency is also used to destroy cancer cells and perform cosmetic treatments to tighten the skin, reduce fat or promote skin cell healing.

Other non-communication applications that use RF energy are things such as microwave ovens, where RF energy is used to heat food. In addition, RF energy can be used for industrial heating and sealing. Industrial heaters and sealers produce radio frequency radiation, which quickly heats the processed material in the same way as microwave ovens for cooking food. Radio frequency energy is also used in industrial fields, such as molding plastic materials, bonding wood products, sealing items (such as shoes and leather bags), and processed foods. Other industrial applications include the testing of RF components and the measurement of material density. Radar is another valuable tool that uses RF energy and is widely used in traffic law enforcement, air traffic control, weather monitoring, and military applications.

Due to the large number of RF applications worldwide, electronic products and systems in life must operate in their electromagnetic environment and cannot emit electromagnetic interference outward. Therefore, before a product or system is put on the market, it must be tested for radio frequency immunity and emission. In order to perform radio frequency immunity testing, the equipment must be exposed to radio frequency interference and magnetic fields, and exhibit a certain field strength and frequency range in its working environment. When testing the radio frequency radiation of a piece of equipment, under normal operation, the radio frequency interference and magnetic field of the equipment will be monitored. For more information about EMC testing, please readWhat is EMC testing?？