Strawmodel 802.11ac Specification Framework Month Year doc.: IEEE 802.11-yy/xxxxr0 Strawmodel 802.11ac Specification Framework Date: 2009-09-22 Authors: John Doe, Some Company

Month Year doc.: IEEE 802.11-yy/xxxxr0 Introduction A draft 11ac specification framework is presented according to the spec framework methodology described in document 09/0237r0 This document is an updated version from the document that was presented in Montreal in May 2009 John Doe, Some Company

11ac Specification Framework Development Month Year doc.: IEEE 802.11-yy/xxxxr0 11ac Specification Framework Development Step 1: TGac specifies Key Technologies and Physical layer Parameters Step 2: TGac specifies Specification Framework according to Framework Specification Methodology Step 3: Form TGac Ad-hoc group(s) to work on Framework elements This document is a first attempt at steps 1&2 John Doe, Some Company

Month Year doc.: IEEE 802.11-yy/xxxxr0 Key Assumptions Build upon 802.11n as much as possible to increase probability of acceptance by the 802.11ac group Use 11n MIMO-OFDM parameters for 20/40 MHz channels same symbol time, number of subcarriers, subcarrier spacing, pilots, guard interval Make data flow as close as possible to 802.11n 11ac MAC changes build upon EDCA Ensure interoperability and coexistence with 802.11n John Doe, Some Company

Top Level Overview of Spec Framework Contents Month Year doc.: IEEE 802.11-yy/xxxxr0 Top Level Overview of Spec Framework Contents 20/40/80 MHz Operation DL MU MIMO UL MU MIMO OBSS Management Multi-Channel Operation Slide 5 Page 5 John Doe, Some Company

Preliminary 11ac PHY Block Diagram Month Year doc.: IEEE 802.11-yy/xxxxr0 Preliminary 11ac PHY Block Diagram John Doe, Some Company

Preambles Purpose Required Inputs Expected Outputs Month Year doc.: IEEE 802.11-yy/xxxxr0 Preambles Purpose Provide training capability for timing, gain setting, frequency synchronization and channel estimation Required Inputs Control parameters: preamble type, bandwidth, number of streams Expected Outputs Preamble samples in frequency domain or time domain Proposed Performance Metrics Length of preamble Coexistence with 11a/n Gain setting accuracy PER versus SNR curves Robustness to front-end impairments Dependencies Choice of channel bandwidth, types of MU-MIMO, maximum number of spatial streams per user Possible Directions Design mixed-mode and/or greenfield preambles to handle MU-MIMO and/or more than 4 spatial streams for a single user John Doe, Some Company

Parsing and Interleaving Month Year doc.: IEEE 802.11-yy/xxxxr0 Parsing and Interleaving Purpose Parse and interleave data per user Required Inputs Encoder output bits Expected Outputs Interleaved bits Proposed Performance Metrics PER versus SNR curves Dependencies Choice of channel bandwidth and maximum number of spatial streams per user Possible Directions Extend 11n interleaver for higher bandwidth and/or more than 4 spatial streams John Doe, Some Company

Coding Purpose Required Inputs Expected Outputs Month Year doc.: IEEE 802.11-yy/xxxxr0 Coding Purpose Provide coding gain Required Inputs Input bits Expected Outputs Coded bits Proposed Performance Metrics PER versus SNR curves Coding/decoding complexity Dependencies None Possible Directions One option to reach the 500 Mbps single-user throughput would be to use a higher coding rate like 7/8 Another choice to make is whether to keep encoding data per user as in 11n, or do per-stream coding John Doe, Some Company

STBC Purpose Required Inputs Expected Outputs Month Year doc.: IEEE 802.11-yy/xxxxr0 STBC Purpose Provide TX diversity Required Inputs Frequency domain QAM subcarrier values per user Expected Outputs STBC encoded subcarrier values Proposed Performance Metrics PER versus SNR curves Dependencies Maximum number of spatial streams per user Possible Directions Extend 11n STBC for more than 4 spatial streams John Doe, Some Company

Spatial Mapping and Cyclic Delays Month Year doc.: IEEE 802.11-yy/xxxxr0 Spatial Mapping and Cyclic Delays Purpose Precode spatial streams in order to provide MU-MIMO or to provide TX diversity or beamforming in case of single-user transmission Required Inputs Frequency domain subcarrier values Expected Outputs Precoded frequency domain subcarrier values Proposed Performance Metrics PER versus SNR curves Dependencies Maximum number of users and maximum number of spatial streams per user Possible Directions MMSE SDMA precoding For single-user transmission, extend 11n cyclic delays for more than 4 spatial streams John Doe, Some Company

Pilots Purpose Required Inputs Expected Outputs Month Year doc.: IEEE 802.11-yy/xxxxr0 Pilots Purpose Phase reference within data symbols Required Inputs Control parameters: number of streams, bandwidth Expected Outputs Pilot values Proposed Performance Metrics PER versus SNR curves Dependencies Choice of channel bandwidth and maximum number of spatial streams per user Possible Directions Extend 11n pilots for higher bandwidth and/or more than 4 spatial streams John Doe, Some Company

Preliminary MAC Spec Framework Overview Month Year doc.: IEEE 802.11-yy/xxxxr0 Preliminary MAC Spec Framework Overview Downlink MU-MIMO Uplink OBSS Management Multi-channel John Doe, Some Company

Downlink MU-MIMO Purpose Required Inputs Expected Outputs Month Year doc.: IEEE 802.11-yy/xxxxr0 Downlink MU-MIMO Purpose Enable efficient MU-MIMO for Downlink Data Transmission Required Inputs NA Expected Outputs Downlink MU-MIMO transmission protocol including Control Message sequence Frame formats and Field Descriptions Coexistence with 11a/n Channel Sounding Protocol UL Block Ack Protocol Link Adaptation Protocol Proposed Performance Metrics Maximum Downlink Data Throughput at the MAC SAP Packet transfer latency from the Tx MAC SAP to Rx MAC SAP Packet loss rate subject to application latency requirements Peak-to-average power of transmitted signal Dependencies Channel sounding protocol Channel reservation protocol for multiple STAs UL Block Ack for multiple STAs VHT SIG Field Design Possible Directions TBD John Doe, Some Company

Uplink MU-MIMO Protocol Month Year doc.: IEEE 802.11-yy/xxxxr0 Uplink MU-MIMO Protocol Purpose Enable efficient MU-MIMO for Uplink Data Transmission Required Inputs NA Expected Outputs Uplink MU-MIMO transmission protocol including Control Message sequence Frame formats and Field Descriptions Coexistence with 11a/n Transmit Power Control Channel Sounding Protocol DL Block Ack Protocol Link Adaptation Protocol Proposed Performance Metrics Uplink Data Throughput at the MAC SAP Packet transfer latency from the Tx MAC SAP to Rx MAC SAP Packet loss rate subject to application latency requirements Dependencies Channel sounding protocol Channel reservation protocol for multiple STAs DL Block Ack transmission to multiple STAs VHT SIG Field Design Possible Directions TBD John Doe, Some Company

OBSS Management Purpose Required Inputs Expected Outputs Month Year doc.: IEEE 802.11-yy/xxxxr0 OBSS Management Purpose Preserve or increase the system throughput of OBSS's when compared to the case of 802.11n OBSS. Required Inputs TBD Expected Outputs OBSS management protocol, which includes a MU-MIMO frame sequence that can set the NAV at an OBSS Proposed Performance Metrics Throughput and delay statistics of OBSS's in the presence of BSS Dependencies Downlink/Uplink MU-MIMO protocol Multichannel protocol Possible Directions Protocol considering multichannel, MU-MIMO and 802.11aa OBSS protocols Dynamic Frequency Selection Transmit Power Control Channel Switching Protocol Slide 16 Page 16 John Doe, Some Company

Multiple Channel Access Month Year doc.: IEEE 802.11-yy/xxxxr0 Multiple Channel Access Purpose Enable access on a set of multiple channels Required Inputs NA Expected Outputs CCA Methodology for multiple channels Protocols for assigning STAs to channels Protocols for aggregating channels to a single STAs Protocols for access on multiple channels Channel Switching Protocol Link Adaptation Frame Formats and Field Descriptions Proposed Performance Metrics Uplink/Downlink Data Throughput at the MAC SAP Channel usage efficiency Packet transfer latency from the Tx MAC SAP to Rx MAC SAP Packet loss rate subject to application latency requirements Dependencies VHT SIG field Block Ack Scheduling Possible Directions Synchronous Contiguous Multi Channel Synchronous Non-Contiguous Multi Channel Asynchronous Non-Contiguous Multi Channel Slide 17 Page 17 John Doe, Some Company