Smart backhauling and fronthauling for 5G networks: from precoding to network architecture [Guest editorial]

The recent widespread use of mobile Internet together with the advent of many smart applications has led to the explosive growth of mobile data traffic in the last few years. This remarkable growing momentum of mobile traffic will most likely continue due to the emerging needs of connecting people, machines, and applications through mobile infrastructure. As a result, the current and projected dramatic growth of mobile data traffic necessitates the development of fifth-generation (5G) mobile communications technology. 5G cellular communications will provide us with the promise of a mobile broadband experience far beyond our current 4G systems. 5G has a broad vision and envisages design targets that include 10???100?? peak date rate, 1000?? network capacity, 10?? energy efficiency, and 10???30?? lower latency. In achieving these expectations, operators and carriers are planning to leverage metro cells and small cells to improve user experience and improve overall network performance. Hence, there is considerable market interest in the development of innovative backhaul and fronthaul solutions for ultra-dense heterogeneous networks that are an evolution of the existing backhaul and fronthaul technologies.