TEM Horn with Magnetic Dipoles
Image of the TEM Horn with Magnetic Dipoles.

The TEM Horn with Magnetic Dipoles often called the ‘Koshelev’ horn or ‘K-antenna’ - has been specifically designed for UWB applications. This horn antenna is referred to as a combined antenna - where an existing antenna type (the TEM horn) has been modified by adding extra physical components to optimise the performance for a certain application. In this case, the TEM horn has been modified by adding a metallic casing and a shorting plate to the structure to improve wideband performance - achieveing a -10dB reflection response over a 11:1 bandwidth

Horn topology with 3 numbered radiators.

As shown in the diagram above, this combined horn can be described as a combination of radiators: an electric type radiator in the form of a TEM horn (1), an active magnetic dipole type radiator (2), and a passive magnetic dipole radiator (3). This structure reduces the lower frequency of the band by approximately 45% when compared to the well-known TEM horn antenna without the shorting plate.

The antenna achieves a -10dB reflection response over an 11:1 bandwidth.

Typical reflection coefficient.