Tunable H-Shaped Microstrip Antenna with Dual Feeding

Abstract EN

The design of a frequency reconfigurable dual-band H-shaped microstrip antenna fed by two coaxial probes is presented.

Each probe excites one of the two fundamental modes of the antenna which are linearly polarized and orthogonal to each other.

The antenna is symmetrically loaded with four varactor diodes to simultaneously tune these two modes.

Simulation results show that the tunable range of the first mode is between 1.69 and 2.19 GHz (1.3 : 1 tuning ratio), whereas it is between 1.94 and 2.72 GHz (1.4 : 1 tuning ratio) for the second mode.

In the range between 1.94 and 2.19 GHz, the radiation of the proposed antenna can be switched between two orthogonal linear polarizations by a simple adjustment to the capacitance of the varactor diodes.

The proposed antenna achieves a good performance in terms of port-to-port isolation, directivity, and cross-polarization.