An Elliptically Polarized Axial-Mode Helical Antenna with a Conformal Polarizer

This paper presents an elliptically polarized axial-mode helical antenna for UHF fuze radar applications with a conformal polarizer. The designed monofilar axial-mode helical antenna is circularly polarized. However, the circularly polarized antennas have polarization mismatch problem in above ground applications like fuze or altimeter radar. Therefore, antennas used in these applications should better be designed as linearly or elliptically polarized in order to obtain moderate received power levels. In this paper, the axial ratio of the designed antenna is increased to 7.6 dB from 1.35 dB at 850 MHz by use of a conformal polarizer. This antenna is measured in an anechoic chamber.