In this paper, three different designs of antenna structures suitable for millimeter-wave applications have been proposed, simulated, and fabricated to meet the desired criteria of future wireless technologies. The effects of varying ground plane dimensions and structures (DGS) over cylindrical dielectric resonators (CDRs) for achieving compact-wideband-multi-resonating frequency antennas have been considered. The first proposed antenna is a two-element CDRs of Rogers RT/Duroid 6010LM mounted on a low-cost FR-4 surface, which enhances the antenna's ability to operate at frequency bands (2 -2.8) GHz, (5.7-7.2) GHz, (9.7-10.8) GHz, and (13.4-14.3) GHz. The second proposed antenna is capable of operating in four different frequency bands: (2.5-3.7) GHz, (7.8-8.5) GHz, (10.5-12) GHz, and (14.6–15.9) GHz. The final proposed antenna permits the antenna to operate in broader and higher frequency bands (6.8–7.8) GHz and (10.5–35) GHz with a fractional bandwidth of 14% and 76.8%, respectively. The reflection coefficient is below -10 dB for all the mentioned frequency bands. All results were simulated using Microwave Studio Software (CST) and High-Frequency Simulator Structure (HFSS). The third proposed antenna was fabricated and compared the measuring results to the related simulation results. This compact-sized antenna has fractional bandwidth, appropriate gain, and a stable radiationpattern over the operating frequency bands. Making it suitable for use in 5G, WiMAX, C-band, X-band, Ku-band, and millimeter-wave (MM-W) wireless applications. Moreover, the proposed antennas are suitable for future sub-6 GHz band applications.