5. Outline
Situating the project
Wireless networks today
Wireless networks tomorrow: cognitive radio
Cognitive radio research
Objectives
Research partners
Milestones
Demos
Regulatory trends & business aspects
5
6. Wireless networks today
A multitude of wireless technologies & standards
building on proprietary or standardized radio technologies
Tuned for a specific application
Many non-interoperable solutions
different architectures
different protocols
Assumption of homogeneous nodes
same protocol stack on all nodes within network
No cooperation between networks
6
7. Internet evolution: multitude of networks
4G communication networks
Evolution towards a “network of networks”,
integrating different technologies
(WLAN, UMTS, Ad Hoc, cellular…)
Characteristics
IP-based
Broadband
Wireless access
Support of mobility
Heterogeneity
…
7
11. Internet evolution:
a multitude of co-located wireless devices
Observation
Growing importance of mobile & wireless networks
Continuous evolution of wireless technologies
Ever increasing number/density of wireless devices
emergence of wireless sensor networks (‘Internet of things’)
Increasing heterogeneity of the Internet
Heterogeneous network technologies
wired & wireless networks
licensed & unlicensed technologies
underutilization of licensed spectrum, scarce unlicensed spectrum
Heterogeneous devices
network interfaces, memory/processing capacity, power supply, fixed/mobile…
Heterogeneous services
Dynamics of mobile and wireless environment
(un)controlled interference, fading, (dis)appearing of devices…
Need for more advanced, more flexible communication paradigms
supporting coexistence of heterogeneous wireless technologies
Cognitive Radio 11
12. Cognitive radio and 4A vision
The 4A vision (ITU) = network ubiquity + connectivity to anything
AnyTIME, AnyWHERE connectivity for Anyone for Anything
AnyTIME connection
For AnyONE
On the move
Night
Daytime
AnyWHERE connection
Between PCs
Human to Human (H2H), not using a PC
Human to Thing (H2T), using generic equipment
Thing to Thing (T2T)
AnyTHING connection
Source: ITU Internet Reports 2005: The Internet of Things 12
13. Cognitive radio and 4A vision
enough spectrum, no matter when
AnyTIME connection (daytime, night, on the move…)
enough spectrum, no matter where
AnyWHERE connection (home, office, indoor, outdoor, at events,
on the move…)
enough spectrum, no matter who (young,
For AnyONE old, skilled, non-skilled…)
enough spectrum, no matter which device
AnyTHING connection (from powerful PCs/laptops up to small
embedded devices with very limited
capabilities).
13
14. Cognitive radio = spectrum sharing
Vertical spectrum sharing
primary users have exclusive spectrum usage rights in a certain band
secondary users either lease or just autonomously use the spectrum
without creating harmful interference to the primaries
Horizontal spectrum sharing
systems/users having equal spectrum usage rights
14
15. Cognitive radio = more flexibility (1)
Radio flexibility (5-tier concept of SDR Forum)
Hardware Radios
no flexibility, fixed functionality
Software Controlled Radios
Fixed signal path
SW interface allows to configure limited number of parameters
(current commercial radios)
Software Defined Radios
SW reconfigurable signal path (current SoA flexible radios)
Ideal Software Radios
more functionality of signal path in digital domain
Ultimate Software Radios
blue sky vision: full programmability with analog/digital conversion
at antenna
15
16. Cognitive radio = more flexibility (2)
Spectrum access flexibility
No flexibility or fixed access
the frequency allocation scheme is fixed at a given time and location
by regulatory bodies
Opportunistic spectrum access
secondary users can actively search for unused spectrum in licensed
bands and communicate using these white holes. There is no
feedback between primary and secondary users.
Dynamic spectrum access
terminals and technologies can negotiate the use of wireless
spectrum locally for a certain time window at run-time. Dynamic
spectrum access requires cooperation and negotiation between
users.
16
17. Outline
Wireless networks today
Internet evolution
Wireless networks tomorrow: cognitive radio
Cognitive radio research
Research areas
Experimentally-driven research
Belgian research efforts on cognitive radio
Conclusions
17
18. Cognitive radio research areas (1)
Sensing the wireless environment
Identification of spectral opportunities
Methods
detection performed in time or frequency domain
different level of knowledge (energy versus feature detection)
different computational complexity and sensing accuracy
18
19. Cognitive radio research areas (2)
(Re)configuration of wireless transmission parameters
Level of collaboration
Level of information sharing
local versus distributed sensing
Local versus global objective span
local versus collective decisions
cross-layer, cross-node, cross-network optimization
cognitive networking
Optimization objective
minimal interference
minimal energy consumption
maximal QoS guarantees (e.g. maximal throughput)
minimal EM pollution
…
19
20. Cognitive radio research
Experimentally-driven research: why?
Dynamic nature of wireless environment
uncontrolled interference
complex wireless channels (mobility, fading…)
(dis)appearing wireless devices
Theoretical studies or network simulations are often unreliable
they build on simplified and inaccurate channel models
they do not take into account HW limitations
Current experiments are limited
experimental platforms and measurements today are mainly based on
1. laboratory equipment, such as vector spectrum analyzers, with high
sensitivity
2. very low-cost narrowband, limited sensitivity off-the-shelf components
only small scale experiments
sensing implementations focused on vertical spectrum sharing
(detection of TV signals)
20
21. Cognitive radio research
Experimentally-driven research: how? (European vision)
Deployment of large-scale open testbed facilities in realistic wireless
environments in view experimental exploration & validation of cognitive
radio and cognitive networking research
Creation of flexible experimental platforms enabling various cognitive
radio usage scenarios
horizontal and vertical spectrum sharing
licensed and unlicensed bands
heterogeneous wireless technologies
Development of benchmarking methods
enabling experiments under controlled and reproducible test conditions
offering automated procedures for experiments and methodologies for performance
evaluation
allowing a fair comparison between different cognitive radio & cognitive networking
concepts or between subsequent developments of diverse approaches
Involvement of relevant stakeholders
academia
industry: equipment manufacturers, network operators, vendors…
regulatory bodies
standardization bodies 21
23. Objectives
Overall research objective
To develop solutions for flexible and efficient use of network/spectrum
resources through appropriate sensing and adaptive/intelligent radio/
network management.
Focus areas
1. Cognitive control functionalities enabling cognitive/opportunistic use of
network/spectrum resources
2. Spectrum sensing functionality for better awareness of the
networking environment
3. E2E energy/power optimization of wireless network and terminal
aspects
4. Flexible and adaptive wireless node (software) architectures
enabling energy-efficient and reliable communication in dynamic,
heterogeneous and large-scale wireless environments
5. Market, standard and policy roadmaps and frameworks for Cognitive
Radio and Opportunistic Radio
23
24. Focus areas
Cognitive control
Cognitive Radio Connectivity-centric Approach
seamless connectivity across heterogeneous wireless networks
(intelligent handover, learning capabilities)
Cognitive Radio Spectrum-centric Approach
Horizontal spectrum sharing
Coexistence of heterogeneous devices in ISM band (IEEE802.11,
IEEE802.15.1, IEEE802.15.4)
Study impact of interference
Interference avoidance techniques
Dynamic spectrum sharing
Vertical spectrum sharing
Opportunistic spectrum sharing (frequency & time)
Coexistence of primary and secondary users
Spectrum sensing functionality
Fast, cost-effective and energy-efficient sensing engine
24
25. Focus areas
End to End Energy Efficiency of Wireless
Networks
Holistic power optimization approach
Radio devices:
innovative implementations of terminals and base stations
power control strategies
Radio transmission (PHY/MAC)
energy-efficient modulation and coding schemes
energy-aware radio link control and scheduling strategies
multi-mode operation and interoperability of coexisting modes
Network architecture
Flexible modular node architecture
avoiding duplicate functionality through a finer granularity of modules
multimode management
information-driven approach (based on information exchanges)
intelligent aggregation of data/control message
HW/SW interaction between HW and SW modules (advanced HAL)
25
27. Focus areas
Market, standard and policy roadmaps
Study transitions in the wireless ecosystem provoked
by introduction of cognitive & opportunistic components
exploring future business, policy and standardization
frameworks in close collaboration with technical developments
Study of changes in interactions between present and new
stakeholders
27
29. Research partners
IMEC/NES
system architecture exploration and definition (wireless link
aspects)
Cognitive Radio Control (MAC) and Sensing solutions
Radio resource management in complex environments
Algorithm development of SoA schemes
Intra-standard (WLAN, WIMAX, 3GPP-LTE, ...) cross-layer controller
Cross-layer energy-aware optimizations
IMEC/WATS
radio coexistence (WBAN-WLAN)
UWB positioning and localization
29
30. Research partners
IBCN
Heterogeneous wireless scenarios in ISM band
Development of adaptive and flexible modular node
architecture incorporating advanced hardware abstraction
layer (HAL) supporting spectrum awareness
Strategies for advanced information sharing and
collaboration (cognitive networking)
Interference avoidance strategies
Dynamic spectrum access
30
31. Research partners
PATS
Seamless handover mechanisms based on sensing
Channel allocation algorithms in a heterogeneous
environment
Cooperation on MAC and Network layer in
heterogeneous environments
Resource sharing in MAC and Network layer in
heterogeneous environments
31
32. Research partners
SMIT
Exploration and evaluation of new cognitive and
opportunistic radio frameworks in business, policy and
standardization, devoting attention to potential
intermediaries and cognitive enablers, in specific:
Intra and inter-firm incentives and bottlenecks for cooperation
Costs of sensing technology
Impact on spectrum use
Analysis of the potential impact of sensing technology and
interference on the cost and revenue models through
specific application scenarios
32
34. Research phases
Step 1: Distributed Coexistence of Heterogeneous
Networks (2009)
Heterogeneous networks awareness through spectrum sensing
Adaptation to minimize harmful interference based on sensing
Step 2: Cooperative coexistence of heterogeneous
Networks (2010)
Communication with heterogeneous networks through SDR
Adaptation to minimize interference based on agreements
Step 3: Collaborative heterogeneous Networks (2011)
Awareness through spectrum sensing
Optimal collaboration to improve user QoS given the spectral (and
energy) resource constraints.
34
35. (Demo) milestones
2009: Distributed Coexistence of Heterogeneous
Networks
Reference scenario: heterogeneous wireless coexistence in ISM band
Spectrum awareness: sensing functionality
sensing multiple channels and multiple communication technologies in the
ISM band
Adaptive modular protocols
distributed interference avoidance algorithm
distributed channel allocation
global routing
optimization of QoS (throughput, reliability)
Integration
Development of HAL incorporating spectrum awareness components
Business Aspects:
Impact of interference (i.e., application QoS degradation) on revenue.
Revenue enhancements from improved coexistence.
35
36. IBBT-IMEC experimental facilities
Heterogeneous ISM test environment @ IBBT
Technologies
commercial radios:
IEEE 802.11 (400)
IEEE 802.15.4 (> 200)
802.15.1 (200)
open USRP software radios (10)
IMEC sensing platform (10)
Spectral range: from 1 MHz to 6 GHz
Bandwidth: 1 MHz to 40 MHz
Benchmarking framework
automated experimentation, performances analysis and
comparison of cognitive radio & cognitive networking solutions
36
41. Minimizing interference
2 WSNs in each others range
Suboptimal routing
Suboptimal use of spectrum
Route optimization by
Resource sharing
Back end routing
will lead to higher spectrum efficiency
Demo
TinySPOTComm
Communication between 2 different sensor nodes, using identical radios
Global routing
1 routing protocol across sensors and back-end network providing overall
connectivity
SunSPOT
TMote
41
43. Wireless Networks towards more Flexible
Spectrum Management?
Current regulatory system of exclusive, long-term
spectrum licensing: inefficiency and high entry barriers
Spectrum underused
Innovation stifled
Customers locked-in
Trend towards technological neutrality & spectrum sharing
Increasing heterogeneity of access technologies (despite LTE)
Huge demand for additional capacity
Digital dividend incites debate on spectrum refarming and sharing
Towards more flexible forms of spectrum management
Dynamic Spectrum Allocation
Spectrum pooling
Secondary markets and change of use
43
44. Cognitive Radio: Technologies to cope with
Flexible Spectrum Management
Cognitive Radio
New paradigm for mobile and wireless
Intelligence and autonomy of networks and handsets
Actively monitor context and change behaviour
In context of Flexible Spectrum Management
Spectrum sensing
Spectrum sharing
Dynamic spectrum allocation
May have repercussions on
Spectrum use
Spectrum cost
User experience
Industry architecture
44
45. Regulatory Trends – WAPECS
WAPECS - Wireless Access Policy for Electronic
Communications (WAPECS)
A framework for the provision of electronic communications
services within a set of frequency bands to be identified and
agreed between European Union Member States in which a range
of electronic communications networks and electronic
communications services may be offered on a technology and
service neutral basis, provided that certain technical
requirements to avoid interference are met, to ensure the
effective and efficient use of the spectrum, and the
authorisation conditions do not distort competition.
45
47. Regulatory Trends – Digital Dividend
Harmonised conditions for the sub-band
790-862 MHz optimised for, but not limited to,
fixed/mobile communications networks
Principle: least restrictive technical conditions
Avoid interference
Facilitate cross-border coordination
47
48. Regulatory Trends – Collective Use of Spectrum
CUS allows an undetermined number of
independent users and/or devices to access
spectrum
in the same range of frequencies
at the same time
in a particular geographic area
under a well-defined set of conditions
48
50. Potential Business Impact
CAPEX and OPEX reduction for Network Operators/
Spectrum Holders
Reduce costs in spectrum
Sub-lease excess capacity in licensed band
Efficient use of spectrum
Diversification of NO’s service portfolio
Better performance and user experience
Increased QoS
Interoperability between services and networks
Cross-country operation: roaming
Increase of service value
50