Design of a Wideband Monopulse Antenna Using Four Conical Helix Antennas

A novel S-band monopulse antenna with four conical helix antennas on a microstrip substrate comparator is designed, fabricated and measured. Conical helix antenna height is 3λ, and comparator size is 130mm×150mm. The bandwidth (SWR <2 dB) of the antenna is 21.3% with an operating frequency range of 2.7 GHz-3.35 GHz. The maximum gain of the sum pattern is 17.4 dB, and the null depths of the difference pattern are less than -30 dB.