A T-Shaped Wide-Slot Harmonic Suppression Antenna

This paper proposes a T-shaped wide-slot harmonic suppression antenna at 4 GHz. Harmonic suppression is achieved by using a narrow microstrip-line-fed and a grounded T-shaped conductor line. The return losses and radiation patterns of the antenna at the fundamental and harmonic frequencies are measured and compared to those of the conventional T-shaped slot antenna. Equivalent circuit models are also presented to give physical insight into harmonic suppression mechanism.