RFantenni

RFantenni are a class of antennas designed to operate at radio frequencies. They serve as the interface between guided RF signals and free-space electromagnetic waves, enabling the transmission and reception of energy in wireless systems.

Antenna performance is described by parameters such as operating frequency, bandwidth, gain, directivity, polarization, radiation pattern, and input impedance. Impedance matching to the transmitter or receiver (often 50 ohms) maximizes power transfer and minimizes reflections.

Common RFantenni types include dipoles, monopoles, loops, patches, Yagi-Uda arrays, log-periodic antennas, horn antennas, helixes, and phased arrays. The choice depends on frequency, size, environment, and required radiation characteristics.

Design considerations include wavelength-based size, electrical length, material and construction, environmental exposure, mechanical robustness, feeding network, and allowable bandwidth. Polarization alignment and mounting orientation influence reception and interference, while regulatory rules govern emissions and safety.

RFantenni enable a wide range of applications, from cellular and Wi‑Fi communications to broadcast transmission, radar, satellite links, RFID systems, and other wireless sensing tasks.

The development of antennas traces back to early experiments with radio waves in the late 19th century, with contributions from Heinrich Hertz and Guglielmo Marconi leading to practical radiocommunication.