Analysis of Circular Polarization of Cylindrically Bent Microstrip Antennas

<table>Equiphase surfaces. (a): The spherical equiphase surface of the flat patch antenna. Semi phase centers coincide. (b): The astigmatic equiphase surface of the E-plane bent patch antenna. <svg height="15.25" id="M25" style="vertical-align:-3.276pt" version="1.1" viewbox="0 0 20.674999 15.25" width="20.674999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.017,0,0,-.017,.062,11.113)"><path d="M619 482q0 -69 -40.5 -119t-96 -72.5t-118.5 -26.5h-44l-70 20l-31 -151q-14 -67 0.5 -83t89.5 -22l-5 -28h-287l8 28q65 7 81.5 22t29.5 83l79 398q12 56 0.5 70.5t-78.5 20.5l7 28h255q108 0 164 -43t56 -125zM524 478q0 141 -146 141q-25 0 -47 -8q-16 -6 -20.5 -13.5
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</svg> (in the <svg height="12.5125" id="M28" style="vertical-align:-3.56265pt" version="1.1" viewbox="0 0 18.4375 12.5125" width="18.4375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>-plane) is behind it. The astigmatism is exaggerated for clarity.</table>

International Journal of Antennas and Propagation

fig6

Figure 6

Figure 6: Analysis of Circular Polarization of Cylindrically Bent Microstrip Antennas 