Wide Impedance Bandwidth Printed Dipole Antenna with Novel Marchand Balun

A broadband printed dipole fed by a balun with third-order impedance matching is proposed in this paper. Firstly, a circuit model of the antenna is given based on the principle of marchand balun. The balun is composed of a stepped impedance microstrip line and marchand balun, which form a three-stage match and its good broadband characteristics are verified by ADS. Furthermore, a printed dipole antenna is integrated using the proposed balun, and the results show that the antenna is obtained a wide impedance bandwidth of 72.7% for VSWR < 2.