Millimeter-wave techniques for 5G mobile communications systems: Challenges, framework and way forward

Millimeter-wave (mmw) transmission has drawn great attentions and is regarded as a key technique in next generation of wireless mobile communications systems (5G). However, the traditional mmw communication system has mainly been applied successfully in indoor scenarios, leaving its outdoor usage an open question. In this paper, how to use mmw frequency in 5G systems outside is considered for both access links and backhaul links. The challenges are analyzed from antenna gains, atmosphere and so on. Possible solutions and way forward are provided.