A Compact Horn Antenna with Low Sidelobes

An X-band (8.2- 12.4 GHz) compact horn antenna based on two shaped horns at the output with a single input horn is proposed. The antenna is matched for VSWR of 2:1 in this frequency range. The antenna is made of lossy aluminum. The sizes of the antenna are 171×86 mm with height of 102 mm. The directivity of the antenna varies between 16.6 to 17.3 dBi. The sidelobes are -30.7 dB and -37.1 dB in the E-plane and H-plane respectively. The gain of the proposed antenna is greater by 2 to 4 dB relatively to the gain of a conventional horn having the same height as that of the proposed antenna, and its sidelobes are lower than the sidelobe of the conventional horn. The simulations were carried by the CST Microwave Studio Software.