This paper presents a wideband circularly polarized broadside radiation characteristics by using stacked rectangular dielectric resonator antenna (DRA) with different volumes. In this designed antenna, the wide input impedance- and axial ratio (AR)-bandwidths come from three factors: stacked rectangular DR with different volumes, stepped-shaped conformal strip associated with microstrip line as a feed and different type of partial ground plane. Here, the orthogonal TE x δ11 and TE y 1δ1 modes have been responsible for the generation of CP radiation in stacked rectangular DRA. Measured results show that the proposed stacked rectangular DRA with different volumes achieves input impedance bandwidth of 54.84% while AR bandwidth has been found to be 11.53%. The proposed antenna provides broadside right-handed CP radiation pattern with gain ranges from 2.27–5.80 dBic and offers an average radiation efficiency of 89.48%, across the entire working bandwidth, respectively. Therefore, this antenna is very much useful for the ISM 2400 band applications. © 2019 Wiley Periodicals, Inc.