Tampere University of Technology Department of Electronics and Communications Engineering W.I.N.T.E.R. Group Wireless Intelligence for Networking Technology by Engineering and Research Compiled by Dr. Sergey Andreev Tampere, Finland July 2014
About Us 2 The group has been formed in January, 2010 Specialized on agile, time-critical, and focused industrially-oriented research Four major projects on beyond-4g (5G) networks 20+ standardization contributions to 3GPP RAN and IEEE 802.16 10+ scientific articles in journals and 40+ conference papers Numerous conferences, seminars, and tutorials on future networking
Major Challenges of Today 3 Increased mobile data traffic, some say 1000x and beyond Growth in connected devices, up to 50 billion devices Diverse requirements and characteristics Current mobile networks are likely to face capacity crunch a new technology that replaces 4G or several (integrated) technologies? Attention shifts to what comes beyond 4G (Fifth Generation!)
What s in a Name? 4 Given a 10-year cycle for every existing generation, we expect 5G systems sometime around 2020 Whereas there is currently no complete definition, 5G may already be understood from the user perspective Human users would like to be connected at all times regardless of their current location take advantage of services provided by multimedia-over-wireless networks
A Glimpse of Tomorrow 5 Main challenge: user s connectivity experience should match service rate requirements and be uniform A comprehensive solution is to deploy the higher density of smaller cells in cellular architecture Network densification generally promises higher bit rates and reduced energy for uplink transmission But licensed spectrum continues to be scarce and expensive, whereas the traditional methods to improve its efficient use approach their theoretical limits!
The Paradigm Shift at Work 6 We expect the majority of near-term capacity and connectivity gains from leveraging unlicensed spectrum Consequently, the incentive to efficiently coordinate between the alternative radio access technologies is growing stronger WLAN becomes an integral part of wireless landscape A Heterogeneous Network (HetNet) employs hierarchical deployment of wide-area macro cells for basic connectivity and coverage augmented with small cells of various footprints and by different RATs to boost capacity
Intelligent Use of Multiple Radio Access Technologies 7 Our focus is on dense HetNets Integration of cellular and WLAN Impact of network densification Advanced interference coordination Potential of WWAN offloading Energy efficient user operation Integrated cellular/wlan deployment Own dynamic system-level simulator 7-cell 3GPP LTE Rel.-10 FDD Features diverse small cells Full support for IEEE 802.11-2012 Event-driven state machine: signal transmission, channel abstraction, traffic and user dynamics, etc. Flexible statistics collection
Current Picture and Perspectives 8 Simulation-based study of multi-radio HetNets Dynamic stochastic geometry analysis Comprehensive system architecture Current focus on integrated deployments Impact of centralized vs. distributed control
Enhanced Spectral Reuse via Device-to-Device Communications 9 We study LTE/WiFi D2D offloading Analysis and system-level simulations Performance requirements and benefits Advanced network-assistance features 3GPP LTE-A & WiFi-Direct demonstration Significant boost in cell throughput (up to 2x) Practical alternative to densification
Current Picture and Perspectives 10 Simulation-based study of network-assisted D2D communication Dynamic system analysis based on stochastic geometry Comprehensive architecture for D2D offloading + MWC 14 DEMO Current focus on emerging applications (vehicular, wearables, etc.) Integrating D2D as an alternative connectivity option under 3GPP
11 Demo: Cellular Offloading onto WiFi Direct Devices receive help from cell during device discovery and D2D connection establishment Secure D2D connectivity between stranger users!
Improved Power Efficiency 12 We concentrate on energy efficiency of a mobile device Optimization of Tx power per radio Recommendations on when each RAT should be used Analysis supported by simulations Efficient practical control algorithms Framework extended to D2D & MTC
Current Picture and Perspectives 13 Use optimization theory to solve energy efficiency problems Rich set of applications across HetNets, D2D, MTC, etc. Current focus on emerging applications (e.g., wireless energy harvesting) Integrating existing energy efficient algorithms into current networks Attractive trade-offs between spectral and energy efficiencies
Efficient Support for Machine-Type Communications in LTE 14 Our goal is to improve LTE support of MTC Large device population w/energy constraints Random vs. scheduled network access Advanced energy/delay/success rate analysis Own detailed protocol-level simulator Efficient small data transmission mechanism Enhancements for idle and connected mode Good energy savings
Current Picture and Perspectives 15 Comprehensive analysis of MTC overload scenario Efficient small data access mechanism: COBALT Extensive support with protocol-level simulations of 3GPP LTE Current focus on coexistence between MTC and H2H Further improvements in channel access, RRM, scalability, etc.
Some of Our Recent Publications 16 S. Andreev, et al., Cellular Traffic Offloading onto Network-Assisted Device-to-Device Connections, IEEE Communications Magazine, April, 2014 S. Andreev, et al., Intelligent Access Network Selection in Converged Multi-Radio Heterogeneous Networks, to appear in IEEE Wireless Communications, 2014 O. Galinina, et al., Optimizing Energy Efficiency of a Multi-Radio Mobile Device in Heterogeneous Beyond-4G Networks, Performance Evaluation, 2014 O. Galinina, et al., Capturing Spatial Randomness of Heterogeneous Cellular/WLAN Deployments With Dynamic Traffic, IEEE J. on Selected Areas in Communications, 2014 A. Pyattaev, et al., Network-Assisted D2D Communications: Implementing a Technology Prototype for Cellular Traffic Offloading, IEEE WCNC, 2014 M. Gerasimenko, et al., Impact of MTC on Energy and Delay Performance of Random-Access Channel in LTE-Advanced, Trans. on Emerging Telecommunications Technologies, 2013 A. Pyattaev, et al., Proximity-Based Data Offloading via Network Assisted Device-to-Device Communications, IEEE VTC-Spring, 2013 S. Andreev, et al., Efficient Small Data Access for Machine-Type Communications in LTE, IEEE ICC, 2013 O. Galinina, et al., Stabilizing Multi-Channel Slotted Aloha for Machine-Type Communications, IEEE ISIT, 2013 A. Pyattaev, et al., 3GPP LTE Traffic Offloading onto WiFi Direct, IEEE WCNC, 2013
Our Research Partners 17 In case of questions, contact: Dr. Sergey Andreev, sergey.andreev@tut.fi Department of Electronics and Communications Engineering, Tampere University of Technology, Tampere, Finland Room TG417, Korkeakoulunkatu 1, 33720 [or P.O. Box 553, 33101] Mobile: +358 44 329 4200 Internet: http://www.cs.tut.fi/~andreev