A Probe-Compensated Helicoidal NF-FF Transformation for Aperture Antennas Using a Prolate Spheroidal Expansion

<table>Dual horn, horizontal polarization, difference pattern. Amplitude of the <svg height="12.325" id="M282" style="vertical-align:-3.56265pt" version="1.1" viewbox="0 0 10.0125 12.325" width="10.0125" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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International Journal of Antennas and Propagation

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Figure 20

Figure 20: A Probe-Compensated Helicoidal NF-FF Transformation for Aperture Antennas Using a Prolate Spheroidal Expansion 