This title provides an in-depth coverage of heterogeneous wireless networks, small cells, and device-to-device (D2D) communications. The authors present performance results for an ideal, partially connected, interference network as well as a practical heterogeneous network, and provide insight into network architecture and performance and details about resource mobility, channel models, and typical and statistical interference modelling. The book also explains leveraging resource heterogeneity in interference mitigation and presents the challenges and feasible solutions for concurrent transmission. Researchers and engineers in the field will find the practical information on LTE and LTE-Advanced, 5G and future network designs particularly interesting and useful.