The technical details of Radio Frequency (RF).
- Definition:
- RF refers to the oscillation rate of electromagnetic radio waves in the range of 3 kHz to 300 GHz. It encompasses both the alternating currents carrying radio signals and the electromagnetic waves themselves.
- These frequencies lie between the upper limit of audio frequencies and the lower limit of infrared frequencies. Additionally, the microwave range is also considered part of the RF spectrum.
- Properties and Applications:
- Electromagnetic Waves: RF waves propagate through space as electromagnetic energy. They are used for various purposes, including communication transmission, broadcasting, and wireless data transfer.
- Skin Effect: RF currents tend to flow along the surface of conductors due to the skin effect. Unlike direct current or lower audio frequency AC, RF currents do not penetrate deeply into conductors.
- Safety: RF currents applied to the body typically do not cause the painful sensation associated with electric shock at lower frequencies. However, they can still cause internal injury and superficial burns.
- Ionization and Conductivity: RF currents can ionize air, creating a conductive path. This property is exploited in applications like electric arc welding.
- Reflection and Standing Waves: RF currents may reflect from discontinuities in cables (e.g., connectors), causing standing waves.
- Transmission Lines: RF currents can be efficiently carried over transmission lines such as coaxial cables.
- Frequency Bands:
- The radio spectrum is divided into bands with conventional names designated by the International Telecommunication Union (ITU). These bands cover various applications, from AM radio to Wi-Fi and beyond.