January 2006 doc IEEE 802 22 060008 r

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January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Cognitive Radio Framework for

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Cognitive Radio Framework for Protection of Primary Users IEEE P 802. 22 Wireless RANs Date: 2006 -01 -16 Authors: Notice: This document has been prepared to assist IEEE 802. 22. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802. 22. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures http: //standards. ieee. org/guides/bylaws/sb-bylaws. pdf including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard. " Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair Carl R. Stevenson as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802. 22 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at patcom@iee. org. > Submission 1 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Presentation Outline • Why

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Presentation Outline • Why distributed sensing is needed • Identifying the components of the cognitive radio framework • Describing what needs to be standardized and what does not • Suggestions on how to move forward Submission 2 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Why Distributed Sensing is

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Why Distributed Sensing is Needed • The WRAN is not allowed to cause harmful interference to a primary user • Based on the WRAN transmit power that defines a protection region around each primary user transmitter in which the WRAN cannot operate • One method of determining if the WRAN is inside the protection region is spectrum sensing • A WRAN is said to be inside the protection region if any of the WRAN stations is within that region Submission 3 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Why Distributed Sensing is

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Why Distributed Sensing is Needed • Because of fading it is possible that one or more the nodes in the WRAN network will receive a signal that has faded significantly and whose receive power is significantly lower than what would be predicted by path loss • There are two types of fading: shadow fading and multipath fading. – Shadow fading is frequency independent and does not change significantly without significant change in location. – Multipath fading is often frequency dependent and can change significantly with small changes in position Submission 4 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Why Distributed Sensing is

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Why Distributed Sensing is Needed • The fading, in particular the shadow fading, results in the hidden node problem, where one node in the network may be inside the protection region but still receive a very weak signal, that would indicate on its own, that the node is outside the protection contour when it is not • To overcome the hidden node problem the network must utilize the results of spectrum sensing from multiple CPEs in order to make a reliable decision as to whether the WRAN network is inside or outside the protection contour • The centralized decision can be made at the base station Submission 5 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Components of the Cognitive

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Components of the Cognitive Radio Framework • Scheduling silent periods for spectrum sensing • Local processing of spectrum sensing data and format of message for this data • Centralized decision function • Method of changing operating channel • MAC Frames for all these functions Submission 6 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Quiet Periods • Need

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Quiet Periods • Need to standardize the scheduling of quiet periods – When are they scheduled relative to data transmissions – What range of durations are required? – Though not necessary for the standard we should probably understand the typical percentage of the time needed for quiet times for robust detection – Possibly a method for synchronizing quiet periods between adjacent cells – MAC Control Frames to manage the schedule Submission 7 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Distributed Decision Framework •

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Distributed Decision Framework • Localized Decision Approach Sensed Signal Local Detector Local Decision Standardize (Possibly Multiple) Submission Standardize Format 8 Centralized Decision Detector Demonstrate at Least one Effective Method Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Distributed Decision Framework •

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Distributed Decision Framework • Local Estimates of Signal Features Approach Sensed Signal Local Processing Standardize (Possibly Multiple) Submission Local Estimate of Signal Features Centralized Decision Detector Local Estimate of Signal Features Standardize Format 9 Demonstrate at Least one Effective Method Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 MAC Control Frames •

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 MAC Control Frames • There a number of MAC Control Frames that need to be defined – – Submission Scheduling quiet periods Requesting spectrum sensing Commands to change operating channel Urgent notification of a locally detected in-band primary user 10 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Summary • The cognitive

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Summary • The cognitive radio framework for distributed decision – Define local decision functions (Standard) – Centralized fusion of localized decisions (Demonstrate at least one effective method) – Define local processing of signals to produce signal statistics (Standard) – Centralized fusion of signal statistics (Demonstrate at least one effective method) Submission 11 Steve Shellhammer, Qualcomm

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Recommendations • I would

January 2006 doc. : IEEE 802. 22 -06/0008 r 0 Recommendations • I would like to recommend we form a tiger team to focus on these various issues • Hold regular conference calls • Flush out the Cognitive Radio Framework • Suggest various techniques for the components of the framework • Evaluate the various techniques Submission 12 Steve Shellhammer, Qualcomm