In this chapter, phased arraysPhased array in the context of full-waveFull-wave solver are investigated. Phased arraysPhased array have assumed a central place in the context of millimetreMillimeter wave wave 5G, cellular architecture systems. Two variants of phased arraysPhased array are popular in the industry. The first is the multi-portPort system and the other is the single portPort arrayArray. In this chapter, a detailed investigation of phased arraysPhased array, in the context of full-waveFull-wave solver is presented. Initially, different types of phased arraysPhased array are presented. The theoreticalTheoretical background of beam forming is also presented in this chapter. The simulationSimulation philosophy behind characterization of phased arraysPhased array is also presented in the chapter. Numerous realReal-world case studies to characterize phased arraysPhased array of different types are discussed.