In this thesis, a wideband Vivaldi antenna for sub-6GHz and beyond for 5G communication applications is proposed. Dual linear polarized antenna arrays can be used to build the base station antenna structure to achieve time division duplex (TDD) or frequency division duplex (FDD) based full duplex (FD) communication system. Through digital beamforming techniques, multiple beams can be scanned to different angles which can inturn be used to communicate with the multiple users simultaneously at different locations. A study of Vivaldi antenna on TMM 10TM substrate is performed. Dual polarized Vivaldi antenna is presented to have the orthogonal pattern and proper isolation for FD communication systems. An egg crate shaped dual polarized 4 × 4 Vivaldi array antenna is designed, optimized, simulated, fabricated, and experimentally measured. The balun of tapered slot Vivaldi antenna and feeding line provides proper impedance matching. Each polarized antenna provides 5GHz to 7.5GHz bandwidth, -20dB isolation, and directional pattern with proper cross-polarization value. The envelope correlation coefficient (ECC) is an important value in MIMO structure. In this design, ECC is less than 0.30 to ensure less interference when the adjacent antennas are radiating. Post-processing of single beam scanning for 4 × 4 and 8 × 8 array antennas from Keysight SystemVue are introduced. The side lobe level (SLL) rises when scanning angle is over 30° at 6.5GHz and 7.5GHz. It is observed that the gain increases when the number of array antenna increases. To improve the SLL, Taylor window of -20dB is selected to suppress the side lobe. SystemVue multiple beams script is adopted to generate four simultaneous beams with different angles φ and θ. The shared array technique can achieve multiple beams scanning in 8 × 8 antenna array. Four simultaneous beams for both polarizations were generated to prove the approach.