The last ten years have witnessed explosive growth in mobile data traffic due to the rapid proliferation of Internet-connected smart devices. For fifth generation (5G) mobile and wireless networks, one of the challenges is how to solve the contradiction between capacity requirements and spectrum shortage. Wide spectrum, mmWave communication is therefore a key enabler for 5G technologies. According to WRC-15, several candidate high frequencies, ranging from 24GHz to 86 GHz, are selected. Recently, US FCC announced several licensed and unlicensed mmWave spectra. mmWave communication is now at the turning point from the concept to implementation. To achieve higher capacity, higher energy efficiency, lower latencies and wider coverage at low cost in 2020, considering 5G application scenarios, it calls for breakthrough in the advanced transceiver structure, implementation techniques, waveform design, network, etc. This special issue offers important contributions in the effort to speed up 5G mmWave communication.
Edited by: Patrick Reynaert, Lianming Li, Qimei Cui, Mikko Valkama and Matin Haenggi