Ultrawideband Spectrally smooth Non-Resonant spherical monopole antenna

Abstract

Antenna with spectrally smooth characteristics over several octaves of bandwidth, is required i) for precise measurement of the spectrum of the cosmic microwave background radiation and ii) to detect imprinted features which reflect various physical processes of the evolving universe. We describe the design of a spherical monopole antenna having spectral-smoothness of the order of 1 part in 104 in the frequency range 40 – 200 Mhz. The structural parameters have been optimized using electromagnetic modeling for minimizing the effects of surface-current- reflections at the terminations of the antenna. This paper presents the simulation results of the prototype developed to validate the concept along with the measurements.