Broadband Compact and Rugged Antenna Designs for Launcher Applications

In this paper, three designs of broadband compact antennas are presented for their application inside metallic launchers. The first antenna is designed using quarter-wave patch with one edge shorted to ground. To reduce frequency of operation, two more antennas are designed using grooves and slits with increased effective electrical length. Second antenna is designed using curved grooves at edges towards length of antenna and third antenna is designed using slits on the surface of the antenna. The Antennas are fed using N-type connector. The three antennas have 21.6%, 11.9% and 6.85% bandwidth for VSWR <= 2 at the center frequency of 1.9, 1.42, and 1.24 GHz respectively. First antenna is fabricated with single block of stainless steel to survive under high shock, vibration and surface temperature of 1000 degree Celsius and its performance is measured.