Theoretical and experimental investigation of smooth and discrete microstrip ring antennas

A rigorous full wave analysis of ring antennas using the integral equation technique is presented. The input impedance and the radiation patterns of both smooth and discrete microstrip ring antennas are calculated for the first two resonance modes (TM/sub 11/ and TM/sub 12/). A full wave analysis using the integral equation technique associated with the method of moments is shown to be a powerful tool for characterizing microstrip ring antennas. It is shown also that the second TM/sub 12/ resonance mode of the ring has a greater bandwidth than that obtained for the first TM/sub 11/ mode. Good agreement is reported between theoretical and experimental results.<
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