Radiotaajuus

Radiotaajuus, often abbreviated as RF, refers to the part of the electromagnetic spectrum that ranges from about 3 kilohertz (kHz) to 300 gigahertz (GHz). This range encompasses radio waves and microwaves. These electromagnetic waves are characterized by their frequency, which is the number of wave cycles that pass a point per second, and their wavelength, which is the spatial distance over which the wave's shape repeats.

RF energy is utilized in a wide variety of technologies. Radio broadcasting, television transmission, and wireless communication systems like Wi-Fi, Bluetooth, and cellular networks all operate within the radio frequency spectrum. Radar systems, which detect objects by emitting radio waves and analyzing their reflections, also rely on RF. Medical applications include radiofrequency ablation, a procedure used to destroy small areas of tissue, and magnetic resonance imaging (MRI), which uses radio waves in conjunction with magnetic fields to create detailed images of organs and tissues.

The propagation characteristics of radio waves vary significantly across the RF spectrum. Lower frequencies can travel long distances and diffract around obstacles, making them suitable for long-range communication. Higher frequencies, on the other hand, tend to travel in straight lines and are more easily absorbed or reflected by objects, which is advantageous for applications requiring directional transmission or localized effects. The allocation and regulation of RF spectrum are managed by international bodies and national agencies to prevent interference between different services.