This paper presents the authors ’vision for 5G wireless systems, which are expected to be standardized around 2020 (IMT-2020). In the future, ubiquitous service will be the key requirement from an end-user ’s prospective, and 5G networks will need to support a vast mesh of human-to-human, human-to-machine, and machine-to-machine connections. Moreover, 5G will need to support these connections in an energy-efficient manner. Various 5G enabling technologies have been extensively discussed. These technologies aim to increase radio link efficiency, expand operating bandwidths, and increase cell density. With these technologies, 5G systems can accommodate a massive volume of traffic and a massive number of connections, which is fundamental to providing ubiquitous services. Another aspect of 5G technology is the transition to an intelligent cloud that coordinates network access and enables flatter architecture.