Presentation is loading. Please wait.

Presentation is loading. Please wait.

Doc.: IEEE 802.11-03/071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 1 A Brief Introduction to the IEEE802.11h Draft TGk Radio Resource.

Similar presentations


Presentation on theme: "Doc.: IEEE 802.11-03/071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 1 A Brief Introduction to the IEEE802.11h Draft TGk Radio Resource."— Presentation transcript:

1 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 1 A Brief Introduction to the IEEE802.11h Draft TGk Radio Resource Measurement January 2003 Simon Black

2 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 2 What is IEEE802.11h? A draft supplement to the IEEE WLAN Standard –Spectrum management in the 5GHz band in Europe Defines mechanisms for dynamic frequency selection (DFS) and transmit power control (TPC) that may be used to satisfy regulatory requirements for operation in the 5GHz band in Europe. A protocol tool-kit for Transmit Power Control (TPC) and Dynamic Frequency Selection (DFS)

3 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 3 Why is IEEE802.11h interesting for Radio Resource Measurement? TPC and DFS involve radio resource measurement! The management model is relevant –Where are the decisions made? –What supporting protocol is required? Some of the management frames & elements may be usable A complete and stable draft exists and is currently undergoing the sponsor ballot process

4 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 4 TPC Service The TPC service provides for the: –Association of STAs with an AP in a BSS based on the STAs power capability –Specification of regulatory and local maximum transmit power levels for the current channel –Selection of a transmit power for each transmission in a channel within constraints imposed by regulatory requirements –Adaptation of transmit power based on a range of information, including path loss and link margin estimates

5 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 5 DFS Service The DFS service provides for: –Association of STAs with an AP in a BSS based on the STAs supported channels –Quieting the current channel so it can be tested for the presence of radar with less interference from other STAs –Testing channels for radar before using a channel and while operating in a channel –Discontinuing operations after detecting radar in the current channel to avoid interference with radar –Detecting radar in the current and other channels based on regulatory requirements –Requesting and reporting of measurements in the current and other channels –Selecting and advertising a new channel to assist the migration of a BSS or IBSS after radar is detected

6 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 6 IEEE802.11h Layer Model MAC Timing Measurement Protocol Measurement Policy Channel Switch Decision Measurement Frames SME MLME Channel Switch Timing PLME MEASURE CHANNEL SWITCH MREQUEST& MREPORT Policy Protocol MLME Frames

7 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 7 IEEE802.11h Management Frames Extensions to existing frames Element based, building on existing IEEE management protocol Beacon/Probe Response extensions –Country –Power Constraint –Channel Switch Announcement –Quiet –IBSS DFS –TPC Report Association/Reassociation Request extensions –Supported Channels –Power Capability

8 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 8 IEEE802.11h Management Frames Action frames Action management frame defined to minimise the number of management frame subtypes used –The IEEE802.11e draft shares this mechanism Defined spectrum management action frames –Measurement Request –Measurement Report –TPC Request –TPC Report –Channel Switch Announcement

9 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 9 Requesting Measurements Requested using Measurement Request Action frame –Dialog Token identifies measurement –Timing can overlap, or be separate from other measurements –Duration of measurement defined in the request –Three measurement types defined Basic CCA (Clear Channel Assessment) RPI (Receive Power Indication) Histogram –Only Basic measurement is mandatory –STA can refuse to perform a measurement even though it may be capable Measurement results returned in a Measurement Report Action frame

10 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 10 Category = 0 (Spectrum Management) Action = 0 (Measurement Request) Dialog Token Activation Delay (Beacon intervals) Measurement Request Element Measurement Offset (TU) Example of Measurement Request Frame Body Format – Basic Request Element ID = 38 (Measurement Request) Measurement Duration (TU) Length = 6 Measurement Token Measurement Request Mode Measurement Type = 0 (Basic Request) Channel Number

11 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 11 Example of Measurement Report Frame Body Format – Basic Report Category = 0 (Spectrum Management) Action = 1 (Measurement Report) Dialog Token Measurement Report Element Measurement Request Element Element ID = 39 (Measurement Request) Measurement Duration (TU) Length = 7 Measurement Token Measurement Report Mode Measurement Type = 0 (Basic Report) Channel Number Map

12 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 12 Measurement Types Basic –Simple flags for BSS, radar, OFDM preamble, unidentified CCA –Fraction of measurement duration CCA was busy RPI Histogram –Distribution of received power density over measurement duration quantised into eight bins

13 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 13 Decision to request measurement from peer STA SME MLME SME IEEE802.11h STA MLME-MREQUEST.req MLME-MREQUEST.ind Decision to accept measurement request from peer STA MLME- MEASURE.req Measurement Process MLME- MEASURE.cfm Compile Measurement Report MLME- MREPORT.req MEASUREMENT REQUEST FRAME MEASUREMENT REPORT FRAME MLME-MREQUEST.cfm MLME- MREPORT.ind MLME- MREPORT.cfm Measurement Request Completed Measurement MSC – STA Accepts

14 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 14 Decision to request measurement from peer STA SME MLME SME IEEE802.11h STA MLME-MREQUEST.req MLME-MREQUEST.ind Decision to refuse measurement request from peer STA or unsupported request MLME- MREPORT.req MEASUREMENT REQUEST FRAME MEASUREMENT REPORT FRAME MLME-MREQUEST.cfm MLME- MREPORT.ind MLME- MREPORT.cfm Measurement Request Completed Measurement MSC – STA Refuses

15 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 15 IEEE802.11h Quiet Interval Facility to quieten BSS –May be used to assist in making measurements without interference from transmissions by members of the BSS May be included in Beacon and Probe Response Frames Quiet interval scheduling –Single, or periodic –Starts at a defined offset from the TBTT –Duration in units of TU (1024us)

16 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 16 IEEE802.11h TPC STAs signal maximum and minimum transmit power capability in Association Request frames AP determines local transmit power constraint (with regard to regulatory requirements) and communicates this in Beacon frames Adaption of transmit power (optional) –TPC request Action frame may be sent to any STA –STA responds with the transmit power used to transmit the TPC response and the link margin for the received TPC request

17 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 17 Decision to adapt transmit power SME MLME SME IEEE802.11h STA MLME- TPCADAPT.req TPC Protocol TPC REQUEST FRAME TPC REPORT FRAME MLME- TPCADAPT.cfm TPC Protocol TPC Adjust MSC

18 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 18 Channel Switching May be used to try and move a BSS to a new operating channel if a radar signal is detected Announced by Channel Switch Announcement Action frame –Broadcast (unacknowledged) –May be transmitted more than once and the information included in Beacon & Probe Response Frames to increase probability of reception Actual channel switch is synchronised to TBTT Facility to quieten BSS until switch occurs

19 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 19 Decision to switch channel SME MLME SME IEEE802.11h STA MLME-CHANNEL SWITCH.req MLME-CHANNEL SWITCH.ind Decision to follow channel switch CHANNEL SWITCH ANNOUNCEMENT MLME-CHANNEL SWITCH.cfm Channel switch complete MLME-CHANNEL SWITCH.resp PLME MLME-CHANNEL SWITCH.cfm PLME-SET Channel switch complete T T CHANNEL SWITCH ANNOUNCEMENT Channel Switching MSC Announcements Repeated in Beacon Frames

20 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 20 IBSS DFS There is no AP function for collating measurements, or coordinating a channel switch The lack of an association protocol means –No exchange of supported channel information –No way to determine membership of the IBSS at a given instant for requesting measurements The IBSS DFS protocol attempts to provide a solution –A DFS Owner service provides a central point of coordination for a channel switch. –Each STA includes a Channel Map field within the IBSS DFS elements that it transmits. This communicates the STA supported channel set and basic measurement reports for that STA. –Best effort due to hidden node issue!

21 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 21 Basis for Radio Resource Measurement? Use the management model Use/adapt/extend some of the MAC Management messages –Measurement request/report mechanism Use the simple TPC principles

22 doc.: IEEE /071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 22 A Brief Introduction to the IEEE802.11h Draft TGk Radio Resource Measurement January 2003 Simon Black


Download ppt "Doc.: IEEE 802.11-03/071r0 Submission January 2003 Simon BlackSimon Black, QosineSlide 1 A Brief Introduction to the IEEE802.11h Draft TGk Radio Resource."

Similar presentations


Ads by Google