Tampere University of Technology Department of Electronics and Communications Engineering

Tampere, Finland

July 2014

Compiled by Dr. Sergey Andreev

W.I.N.T.E.R. Group

Wireless Intelligence for Networking Technology by

Engineering and Research

About Us

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

2

3

Major Challenges of Today

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!)

4

What’s in a Name?

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

5

A Glimpse of Tomorrow

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!

6

The Paradigm Shift at Work

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

7 Intelligent Use of

Multiple Radio Access Technologies

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

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

8

Current Picture and Perspectives

• 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

9 Enhanced Spectral Reuse via

Device-to-Device Communications

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

Demo: Cellular Offloading onto WiFi Direct 11

Devices receive help from cell during device

discovery and D2D connection establishment

Secure D2D connectivity

between stranger users!

12

Improved Power Efficiency

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

13

Current Picture and Perspectives

• 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

14 Efficient Support for

Machine-Type Communications in LTE

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

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

16

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