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Dual Frequency Ring Antennas with Coplanar Capacitive Feed

By Veeresh G. Kasabegoudar
Progress In Electromagnetics Research C, Vol. 23, 27-39, 2011


In this paper, design of a coplanar capaciπtive coupled probe fed microstrip ring antenna for dual frequency operation is presented. The proposed antenna is excited by a single probe feed connected to a capacitive feed strip placed along one of the radiating edges of the ring antenna. The coplanar capacitive feed strip is modified to obtain the best possible match with the antenna input impedance and to tune out the excessive capacitive reactance due to feed strip. It is also demonstrated that the modified feed strip can be placed either inside or outside the ring and similar radiation characteristics can be obtained at both the resonant frequencies. Ring dimensions decide the resonant frequencies values and their separation. Measured data fairly agree with the simulated characteristics.


Veeresh G. Kasabegoudar, "Dual Frequency Ring Antennas with Coplanar Capacitive Feed," Progress In Electromagnetics Research C, Vol. 23, 27-39, 2011.


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