Millimeter-wave (mm-wave) technology is a viable candidate to address the growing data traffic in 5G wireless communication and beyond. However, challenges related to free-space propagation loss, atmospheric absorption, scattering, and nonline-of-sight propagation must be addressed to benefit from the promised bandwidth available in the mm-wave regime. In this context, phased-array technology is considered vital to provide high-speed and seamless wireless solutions to the industry. A phased array can be defined as a multiple-antenna system that electronically controls the radiated electromagnetic (EM) beam. The official origin of the antenna array concept is attributed to Guglielmo Marconi. A repeated Morse code signal letter “S” from Poldhu, United Kingdom to St. John’s in Canada was successfully demonstrated in December 1901, using a two-element antenna array. In the early 1940s, Luis Walter Alvarez designed the first electronically scanning phased-array radar. Both scientists were awarded the Nobel Prize for their discovery.