Multi Level Power Control 2007-5-15 Multi Level Power Control Date: 2007-05-15 Authors: Notice: This document has been prepared to assist IEEE 802.11. 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 802.11. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures <http:// ieee802.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 <stuart@ok-brit.com> 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 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at <patcom@ieee.org>. Floyd Backes, AutoCell Laboratories, Inc.

2007-5-15 Abstract Abstract This presentation summarizes a submission on multi-level power control, 11-07-0465-02-000v-multi-level-power-control. Floyd Backes, AutoCell Laboratories, Inc.

Presentation Overview 2007-5-15 Presentation Overview Review of Transmit Power Control AP Power Control STA Power Control Simulation Explanation Simulation Results Multi Level Power Control Overview of Contribution Floyd Backes, AutoCell Laboratories, Inc.

Transmit Power Control 2007-5-15 Transmit Power Control Unlike TPC for regulatory purposes, this submission is intended to allow for increased performance A variety of algorithms for performance based TPC exist This submission does not specify an algorithm Floyd Backes, AutoCell Laboratories, Inc.

Simple Example 2007-5-15 AP 1 AP 2 Non-AP 1 Non-AP 2 Floyd Backes, AutoCell Laboratories, Inc.

2007-5-15 Simple Example Transmissions from AP2 interfere with Non-AP 1 AP 1 AP 2 Non-AP 1 Non-AP 2 TPC Reduces Interference Floyd Backes, AutoCell Laboratories, Inc.

What About the non-AP STAs? 2007-5-15 What About the non-AP STAs? AP 1 AP 2 Non-AP 1 Non-AP 2 Non-AP 1 still interferes with AP2 Non-AP STA TPC can additionally reduce interference Floyd Backes, AutoCell Laboratories, Inc.

Simulation Results Bear This Out 2007-5-15 Simulation Results Bear This Out Custom 802.11 network simulation tool used to investigate performance impact of TPC No TPC AP only TPC AP + non_AP TPC 4 runs for each combination 802.11 b/g environment 8 Detached Homes 2 Video streams (3.5 Mbps) in each homes Floyd Backes, AutoCell Laboratories, Inc.

2007-5-15 Physical Layout Floyd Backes, AutoCell Laboratories, Inc.

Network Configuration 2007-5-15 Network Configuration Floyd Backes, AutoCell Laboratories, Inc.

2007-5-15 Traffic Floyd Backes, AutoCell Laboratories, Inc.

Simulation Results 2007-5-15 Percent PDU Error Rate Floyd Backes, AutoCell Laboratories, Inc.

Other Considerations Clearly, TPC can improve performance 2007-5-15 Other Considerations Clearly, TPC can improve performance There can be a down side… Floyd Backes, AutoCell Laboratories, Inc.

Previous Example 2007-5-15 AP 2 coverage before TP reduction New station now appears in what is now a coverage hole AP 1 AP 2 Non-AP 1 Non-AP 2 Floyd Backes, AutoCell Laboratories, Inc.

Eliminating TPC induced Coverage Holes 2007-5-15 Eliminating TPC induced Coverage Holes If TP of both data and management frames from an AP are reduced, a non-AP STA within “range” of that AP may not hear its Beacons Multi Level Power Control allows Management frames to be transmitted at a higher TP than data Floyd Backes, AutoCell Laboratories, Inc.

Previous Example 2007-5-15 Range of Beacons Range of Beacons Newly arrived Non-AP STA Can hear AP2’s beacons AP 1 AP 2 Non-AP 1 Non-AP 2 Floyd Backes, AutoCell Laboratories, Inc.

Summary of Submission Provides: 2007-5-15 Summary of Submission Provides: The ability to signal control of the transmit power of data frames independently of management frames coming from non-AP STAs The ability to control all of the STAs in a BSS simultaneously, or on a per-STA basis. The ability to signal the management power setting before joining a BSS Signal the management power setting immediately upon joining a BSS The ability for a non-AP STA to signal whether or not it can adopt the transmit power limit and if not, what its limit is. Floyd Backes, AutoCell Laboratories, Inc.

What this is not Dynamic TPC 2007-5-15 What this is not Dynamic TPC This submission does not specify a power control algorithm May be used even when transmit power is adjusted manually Floyd Backes, AutoCell Laboratories, Inc.

Rationale Adjustment of Transmit Power common in 802.11 deployments 2007-5-15 Rationale Adjustment of Transmit Power common in 802.11 deployments Spatial reuse enhancements in dense deployments Enhanced privacy Power savings Redundancy Transmit Power may be adjusted as a result of: Manual planning Assisted site surveys Automatic power adjustment algorithms Floyd Backes, AutoCell Laboratories, Inc.

Approach Create new IE for “Relative Power Limit Request” 2007-5-15 Approach Create new IE for “Relative Power Limit Request” Represents a reduction in power limit (relative to country and local power constraint), in dB Not possible to extend existing power constraint IE Relative Power Limit Request IE to be carried in Beacons Association Responses Reassociation Responses Probe Responses Relative Power Limit Request frame Floyd Backes, AutoCell Laboratories, Inc.

Approach (continued) Create new IE for “Relative Power Limit Response” 2007-5-15 Approach (continued) Create new IE for “Relative Power Limit Response” Represents the power limit actually in use A “Status”, one of: Accept Reject (requested relative power limit out of bounds due to HW limitations, regulatory limitations, or management configured limitations) If “Reject”, what maximum relative power limit can be supported Relative Power Limit Response IE to be carried in: Relative Power Limit Response frame Floyd Backes, AutoCell Laboratories, Inc.

Approach (continued) 2007-5-15 New Wireless Network Management Action frame for “Relative Power Limit Request” New action field value for “Relative Power Limit Request” Carries the Relative Power Limit IE May be broadcast or unicast A directed Transmit Power Limit frame overrides any value carried in a Management frame If the non-AP STA cannot support the requested Relative Power Limit, it responds with the actual value that can be supported using the Relative Power Limit Response element. STA must use the lower of: the maximum transmit power level specified for the channel in the Country element minus the relative power limit specified for the current channel (from the MIB) in the Relative Power Limit Request element the maximum transmit power level specified for the channel in the Country element minus the local power constraint specified for the channel (from the MIB) in the Power Constraint element. Floyd Backes, AutoCell Laboratories, Inc.

Summary of Submission 2007-5-15 New Wireless Network Action frame “Relative Power Limit Request“ Carries Relative Power Limit Request IE New Wireless Network Action frame for “Relative Power Limit Response“ Carries Relative Power Limit Response IE May be sent in response to a Relative Power Limit request frame Association Response Reassociation Response Define Relative Power Limit Request and Relative Power Limit Response IEs. Add relative Power Limit Request IE to: Beacon Frame Body Association Response Frame Reassociation Response Frame Probe Response Frame Floyd Backes, AutoCell Laboratories, Inc.

Summary of Submission (continued) 2007-5-15 Summary of Submission (continued) Added Relative Power Limit to the BSS Description table in MLME-SCAN.confirm Added Relative Power Limit Request to the parameter Lists of: MLME-ASSOCIATE.confirm MLME-ASSOCIATE.response MLME-REASSOCIATE.confirm MLME-REASSOCIATE.response Floyd Backes, AutoCell Laboratories, Inc.

2007-5-15 Summary of Submission Define Relative Power Limit Request Protocol Exchange Define primitives: MLME-POWERLTREQUEST.request MLME-POWERLTREQUEST.confirm MLME-POWERLTREQUEST.indication MLME-POWERLTRESPONSE.request MLME-POWERLTRESPONSE.confirm MLME-POWERLTRESPONSE.indication Define Relative Power Limit Request and Response Procedure Floyd Backes, AutoCell Laboratories, Inc.

Motion Move to include the substantive text in document 2007-5-15 Motion Move to include the substantive text in document 11-07/0465r0 into the TGv draft. Moved: Seconded: Floyd Backes, AutoCell Laboratories, Inc.