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3 - The 5G architecture
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- By Heinz Droste, Deutsche Telekom, Icaro Leonardo Da Silva, Ericsson, Peter Rost, Nokia, Mauro Boldi, Telecom Italia
- Edited by Afif Osseiran, Jose F. Monserrat, Patrick Marsch
- Foreword by Mischa Dohler, King's College London, Takehiro Nakamura
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- Book:
- 5G Mobile and Wireless Communications Technology
- Published online:
- 05 June 2016
- Print publication:
- 02 June 2016, pp 50-76
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Summary
Introduction
The design of a mobile network architecture aims at defining network elements (e.g. Base Stations [BSs], switches, routers, user devices) and their interaction in order to ensure a consistent system operation. This chapter discusses basic considerations and provides an overview of current research activities. Network architecture can be considered from different angles that are needed in order to fulfill objectives like integration of technical components into an overall system, proper interworking of multi-vendor equipment and efficient design of physical networks from cost and performance point of view.
As 5G systems have to integrate a plethora of partly contradicting requirements, enablers such as Network Function Virtualization (NFV) and Software Defined Networking (SDN) are to be applied in order to provide the needed flexibility of future networks, especially for the core network. Applying these tools may require a rethinking of some traditional aspects of network architecture design. This chapter will give the reader an impression of the most important topics influencing architecture design of future networks.
NFV and SDN
Today's operator networks include a large and increasing variety of hardware appliances. Launching new services often requires integration of complex hardware dedicated to the service including costly procedure design and is associated with lengthy time to market. On the other hand, hardware life cycles become shorter as technology and service innovation accelerates.
At the end of 2012, network operators have started an initiative on NFV [1]. NFV aims at consolidating the variety of network equipment onto industry-standard high-volume servers. These servers can be located at the different network nodes as well as end-user premises. In this context, NFV relies upon but differs from traditional server virtualization. Unlike server virtualization, Virtualized Network Functions (VNF) may consist of one or more virtual machines running different software and processes in order to replace custom hardware appliances (Figure 3.1). As a rule, multiple VNFs are to be used in sequence in order to provide meaningful services to the customer.
NFV requires an orchestration framework that enables proper instantiation, monitoring and operation of VNFs and Network Functions (NFs) (e.g. modulation, coding, multiple access, ciphering, etc.).
11 - Green communications in cellular networks with fixed relay nodes
- from Part III - Relay-based cooperative cellular wireless networks
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- By Peter Rost, NEC Euro Labs, Germany, Gerhard Fettweis, Technische Universität Dresden, Germany
- Edited by Ekram Hossain, University of Manitoba, Canada, Dong In Kim, Vijay K. Bhargava, University of British Columbia, Vancouver
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- Book:
- Cooperative Cellular Wireless Networks
- Published online:
- 03 May 2011
- Print publication:
- 10 March 2011, pp 300-323
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Summary
Introduction
Mobile communication systems have to provide exponentially increasing data rates for an increasing number of subscribers using ubiquitous data services. As the capacity per cell is limited by the available bandwidth, the same time frequency resources must be spatially reused. Hence, the more the user density increases, the higher the spatial reuse must be to satisfy the demand for high data rate services. This chapter discusses relaying as a candidate technology to increase the spatial reuse and therefore to provide the required data rates while reducing energy consumption in mobile communication systems.
Two motivating examples
A challenging property as well as an opportunity for exploiting the wireless channel is nonlinear signal attenuation (path-loss), which offers the possibility to concentrate power at certain points in the network and spatially reuse resources within a mobile communication network. Consider an additive white Gaussian noise (AWGN) channel with a path-loss exponent α = 4, receiver noise power N, and transmission power P. Given these qualities and assuming a downlink transmission where a terminal can use the received signals from each radio access point (RAP), the observed signal-to-noise ratio (SNR) at a normalized distance d is given by ρ(d) = Σi P/N · |di − d|−α, where di is the position of the ith RAP.