A compact annular slot monopole antenna with coplanar waveguide feeding is proposed in this work. The designed antenna has simple structure, consisting circular shaped radiating element on a square tuning stub. The overall dimension of the antenna comes around 20´20´1.6mm on FR4 substrate with dielectric constant 4.4. The impedance matching and the radiation characteristics of the designed structure are investigated using finite element method based HFSS tool. The miniatured design indicates an embedded circular strip connected to square stub through 50 ohms feed line. The resonant bands of the proposed prototype show the band side radiation patterns with maximum antenna gain of 3.2dB and directivity around 4dB.

annular slot, circular strip, finite element method, monopole antenna, tuning stub.