Heterogeneous and small cell networks: part 1 [Guest Editorial]

Driven by a new generation of wireless user equipment and the proliferation of bandwidth-intensive applications, user data traffic and the corresponding network load are increasing in an exponential manner. Most of this new data traffic is being generated indoors, which requires increased link budget and coverage extension to provide satisfactory user experience. As a result, current cellular networks are reaching their breaking point, and conventional cellular architectures that are devised to cater to large coverage areas and optimized for homogeneous traffic are facing unprecedented challenges to meet these user demands.