Biconical Antenna 4 dBi Typ. Gain, 2-18GHz Frequency Range RM-BCA218-4

A biconical antenna is a classic type of broadband antenna. Its structure consists of two conical conductors placed tip-to-tip, typically employing a balanced feed. It can be visualized as the flared end of an infinite, balanced two-wire transmission line fed at its center, a design that is key to its wideband performance.

Its operating principle relies on the conical structure providing a smooth impedance transition from the feed point to free space. As the operating frequency changes, the active radiating region on the antenna shifts, but its fundamental characteristics remain consistent. This allows it to maintain stable impedance and radiation patterns over multiple octaves.

The key advantages of this antenna are its very wide bandwidth and its omnidirectional radiation pattern (in the horizontal plane). Its main drawback is its relatively large physical size, especially for low-frequency applications. It is widely used in Electromagnetic Compatibility (EMC) testing, radiated emissions and immunity measurements, field strength surveys, and as a broadband monitoring antenna.