radiofrequente

Radiofrequente (RF) refers to the portion of the electromagnetic spectrum with frequencies roughly from 3 kHz to 300 GHz. RF waves can carry information through air or through guided media (coaxial cables, waveguides) and are used in many wireless and wired communications.

Applications include radio broadcasting, mobile telephony, Wi‑Fi and Bluetooth, satellite communications, radar, RFID and NFC, industrial heating, medical diathermy, microwave ovens, and radio astronomy.

Technical aspects involve generation by oscillators and amplifiers, modulation to convey data, and antennas to radiate and receive signals, as well as transmission lines or waveguides. Propagation depends on frequency; lower RF tends to longer range and better diffraction, while higher RF often relies on line-of-sight or guided channels. Interference management and electromagnetic compatibility (EMC) are important considerations in design and operation.

Safety and regulation cover exposure limits to protect people from excessive energy absorption (SAR) and general public exposure. Spectrum allocations and licensing are managed by international bodies (such as the ITU) and national regulators, with standards from organizations like ICNIRP and IEC. EMC rules seek to prevent interference between devices and systems.

History highlights include early experiments by Heinrich Hertz that demonstrated RF waves, followed by the development of practical wireless communication by Guglielmo Marconi and others. The RF domain expanded through broadcasting, radar during the mid-20th century, and the digital era with cellular networks, Wi‑Fi, and modern wireless technologies.