Recent research in cloud radio access network (C-RAN) for 5G cellular systems - A survey

Traditional architectures of cellular networks are facing tremendous challenges due to unprecedented increase in mobile data traffic, limited spectrum availability and high power consumption. In light of this, industries as well as research communities are in constant search for fundamental breakthroughs in developing novel network architectures for supporting the exploding user demand, while reducing capital and operational expenditures for network operators. Cloud radio access network (C-RAN) architecture is such a paradigm shifting concept for cellular networks, which is also being actively considered as a major candidate for future 5G cellular systems. This paper presents a comprehensive survey on the most recent advances in C-RAN research focusing on the analysis and enhancement of its various major aspects. In particular, after reviewing the works on C-RAN architectures, we then focus on the papers published specifically on the throughput enhancement, interference management, energy efficiency, latency, security and system cost reduction of C-RAN based cellular networks. A summary of the open issues and future research directions in these areas of C-RAN based cellular networks is also presented.