F-matrix for a coaxial feed in a microstrip patch antenna

In the LN-PC hybrid technique, numerical analysis method for microstrip patch antennas of arbitrary shape, the regions under and outside of the patch are solved separately by means of the theory for planar circuits (PC) and the theory for linear antennas (LN), respectively, and the two solutions are matched at the boundary. Although it leads to reasonably good results, more elaborate studies are desired concerning the patch edge and the coaxial cable to a planar circuit junction. The latter problem is dealt with, and the F-matrix representation of the junction is presented together with a few numerical examples. The input impedance is calculated by means of the present theory for a circular microstrip antenna.<
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