Image of the Discone.

The discone antenna is a monopole variation of the biconical antenna using a small ‘ground plane’, therefore the discone is a modified dipole shape. Dipole modifications are often used to obtain wide-band operation without greatly increasing complexity. Wide angle biconical antennas are popular for their wide impedance bandwidth and omnidirectional radiation coverage. The discone variation may be preferred when the reduced physical size or radiation mainly in one half-space is required.

A discone is one half of a biconical antenna driven with respect to a small ground plane. The discone differs from the monocone primarily in the size of the ground plane. The monocone’s ground plane is relatively large in order to emulate an infinite ground plane, while the discone has a much smaller ground plane that influences antenna performance much more directly. The smaller ground plane provides a size and weight advantage over the monocone while still providing acceptable broad-band performance.