The real-time adjustment of spectrum utilization in response to
changing circumstances and objectives. NOTE Changing circumstances
and objectives include (and are not limited to)
energy-conservation, changes of the radios state (operational mode,
battery life, location, etc.), interference- avoidance (either
suffered or inflicted), changes in environmental/external
constraints (spectrum, propagation, operational policies, etc.),
spectrum-usage efficiency targets, quality of service (QoS),
graceful degradation guidelines, and maximization of radio
lifetime. **From IEEE P1900.1-2008
Slide 3
a) A set of rules governing the behavior of a system. NOTE 1
Policies may originate from regulators, manufacturers, developers,
network and system operators, and system users. A policy may
define, for example, allowed frequency bands, waveforms, power
levels, and secondary user protocols. B) A machine interpretable
instantiation of policy as defined in (a) NOTE 2 Policies are
normally applied post manufacturing of the radio as a configuration
to a specific service application. NOTE 3Definition b) recognizes
that in some contexts the term policy is assumed to refer to
machineunderstandable policies. **From IEEE P1900.1-2008
Slide 4
a) A type of radio in which communication systems are aware of
their environment and internal state and can make decisions about
their radio operating behavior based on that information and
predefined objectives. NOTEThe environmental information may or may
not include location information related to communication systems.
b) Cognitive radio [as defined in item a)] that uses
software-defined radio, adaptive radio, and other technologies to
adjust automatically its behavior or operations to achieve desired
objectives.
Abstract: Cognitive and next generation radio technology is
instrumental in handling the dynamic nature of spectrum management.
Efficient use of spectrum is essential because there is more
competition for licensed and unlicensed spectrum and it is being
divided up to more stakeholders. There are two distinct changes in
the area of spectrum management. The first is the availability of
white space (broadcast) spectrum bands that was freed up by the
conversion to digital TV. The second is the United States
government broadband plan, which involves selling off some of its
licensed spectrum for profit. This greatly affects the military,
which now has a much smaller piece of the spectrum pie. How can
Semantic Web technology improve this? We need an ontology that can
define radio characteristics and define a policy ontology framework
to manage the dynamics changes in a radio system. If there was a
common ontology, all the devices involved in a radio system and
between radio system would be able to share information
easier.
Slide 8
We also need these ontologies to be able to search the spectrum
databases for available white space spectrum. These databases will
be accessed over the internet. There are many stakeholders affected
by the spectrum changes, such as 1) commercial wireless and
networking product suppliers: they need to know how to search for
available spectrum to use in their local devices; 2) military: need
to efficiently use their smaller spectrum band; 3) Federal
Communications Commission: they need to be able to propagate
spectrum changes easily to consumers and make sure that users and
suppliers are following the rules; 4) public safety domain: they
need an easier way to taker over spectrum in emergencies; and
lastly, 5) the general public: who wants all their wireless devices
to work all the time.
Slide 9
I do not propose to solve all these issues but to apply the
knowledge and tools defined in this course to create a starting
point that can be carried on in my IEEE working group (P1900.5) for
completion and publication in a standard that could be accepted by
the stakeholders mentioned. The demonstration of this project will
involve creating a subset policy ontology and a way to query the
white space database service for available spectrum. Some of the
devices needing spectrum could be personal area networking devices
for medical purposes.
Slide 10
Create Policy Ontology subset of Kaos with Protege; Tie in
existing radio ontology create by Wireless Innovation Forum MLM
working group. Create white space database interface; Create
queries to white space database; Demonstrate receiving results of
available white space and having that information disseminate to
devices using policy Document results.
Slide 11
Actors White Space database service Radio-enabled network
device (CR) Policy Manager Reasoner Software Control Policy
Enforcer
Slide 12
White Space DB Service Access Use case Diagram
Slide 13
Cognitive Radio Use Case Diagram
Slide 14
White Space devices, be they access points or clients, will
operate in TV-broadcast spectrum that isn't being used locally.
When a White Space device is switched on it connects, over the
internet, to a chosen database and supplies its location. The
database responds with a list of radio frequencies that are
available locally. The Policy Manager selects one (or more) to use,
and passes that information on to the CR. The CR then uses that
frequency to communicate on a particular channel.
Slide 15
Use requirements from P1900.5 standard - IEEE Standard Policy
Language Requirements and System Architectures for Dynamic Spectrum
Access Systems Some of the entities: Policy Set Policy Rule Policy
Effectivity Time Location Policy Action Use subset of Kaos policy
ontology
Slide 16
The Kaos policy Ontology was created under DARPA/NASA
sponsorship. The current version of KAoS Policy Ontologies
(http://ontology.coginst.uwf.edu/) defines basic ontologies for
actions, actors, groups, places, various entities related to
actions (e.g., computing resources),and policies. I have loaded
this into Protg as shown.
Slide 17
Use API definition from actual white space database service at
Spectrum Bridge; After the access point registers with the white
space database, the list of available frequencies are returned for
use in the CR devices.
Slide 18
Slide 19
Slide 20
Created ontologies in Protg; Created Java code to: Use Jena for
ontologies. Create test code to simulate: Querying white space
database for available spectrum; Policy creation sent to CR using
policy ontology. Results will be documented in final paper.