Broadband compact series-fed dipole pair antenna with simplified integrated balun

A broadband compact series-fed dipole pair (SDP) antenna using a simplified integrated balun is presented. The proposed integrated balun is simple compared to a conventional balun and consists of a microstrip line inserted on a coplanar strip (CPS) line, along the center of the CPS. When the proposed balun is incorporated into the SDP antenna, it creates an additional resonance due to a slot in the CPS line at high frequency as well as two resonances by the two dipoles with different lengths, and enhances the antenna's bandwidth. The proposed antenna exhibits a measured impedance bandwidth of 58.5% (1.62–2.96 GHz) for a VSWR < 2, a stable gain of 6.1 ± 0.5 dBi, and a front-to-back ratio > 14 dB within the bandwidth.