Experimental validation of NEC analysis of software models of tape wound helical satellite antennas

This paper is about the validation of modeling software that was developed to analyze and predict the theoretical performance of helical antennas in general and in particular those antennas using a metallic strip or tape as radiating elements. This was applied to uniform cylindrical helices as well as tapered helices with a single pitch angle and novel dual pitch antennas. Corresponding helices were built and tested. The experimental performances are in very good agreement with the theoretical results. This was investigated for helices working in the axial mode in near circular polarization with axial ratios between 1 and 2 dB and return loss better than 20 dB. This validation of the software, using Kraus' (1988) criteria for the equivalence of a tape element to a wire, against experimental results is providing a new, powerful, and accurate tool for reliably designing helical antennas, a much needed tool. This validation for tape helical antennas is particularly significant for space applications where deployability is required and optimization of the mass, site and gain of the antenna are essential.