CONTEXT

The invention seeks to improve the gain antennas of EBG material with a side wall surrounding an axis.
The introduction of a break (or defect) into the geometric periodicity of the EBG material makes it possible to produce an absorption defect and hence to create a narrow passband within a wide stopband.
The EBG material antennas have the advantage of having a very good directivity with reduced dimensions (2D) compared to dish, lens or horn-type antennas. The EBG antenna allows multifunctional modes (multiband and multipolar).

TECHNICAL DESCRIPTION

The invention seeks to improve the gain antennas of EBG material with a side wall surrounding an axis.
A antenna made from a EBG (Electromagnetic BandGap) material, includes: a lateral wall (4) which is made from an EBG material and which completely surrounds a central axis (6), the wall being disposed at a distance from the central axis such as to form a central resonant cavity; and at least one radiating element (34) which is placed inside the cavity.
Each radiating element is positioned inside the cavity in order to excite an electromagnetic field parallel to the central axis and the radiating element(s) can excite the modes of the central cavity having a radial resonance more strongly than the other modes of the cavity.

BENEFITS

• Omnidirectional
• Very good gain (about 8 times better than similar antennas with dipole for example)
• Possible use of metal EBG material (less expensive than a dielectric EBG material)

INDUSTRIAL APPLICATIONS

Antenna useful for base station in mobile telephony