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Project: IEEE P802.11b Working Group for Wireless Local Area Networks (WLANs) Submission Title: [MBCK TGg Option] Date Submitted: [ 15 November 2001 ] Source: [ T. O’Farrell, L.E. Aguado & C. Caldwell] Company [Supergold Communication Ltd. ]
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Project: IEEE P802.11b Working Group for Wireless Local Area Networks (WLANs) Submission Title: [MBCK TGg Option] Date Submitted:[ 15 November 2001 ] Source: [ T. O’Farrell, L.E. Aguado & C. Caldwell] Company [Supergold Communication Ltd. ] Address [ Leeds Innovation Centre, 103 Claredon Road, Leeds 2, U.K. ] Voice:[ +44 113 233 2052 ], FAX: [ +44 113 233 2032 ], E-Mail:[ tim.ofarrell@supergold.com ] Re: [ Physical layer modulation proposal for the Higher Rate Extension to 802.11b Standard] Abstract: [ This contribution is a presentation of Supergold’s MBCK TGg option] Purpose: [ Proposal for the Higher Rate Extension to 802.11b Standard] Notice: This document has been prepared to assist the IEEE P802.11. 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 acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.11. O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
“CCK and OFDM” in 2.4 GHz Band MBCK TGg Option O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
Outline of the Presentation • The case for Single Carrier Modulation • The Co-existence Issue • The case for MBCK • The MBCK Option O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
Single Carrier MBCK • MBCK supports 802.11g’s expected service repetoire by offering 22 and 30 Mbps high rate extensions to CCK using a single carrier modulation technique termed SC-MBCK • Under the proposed “CCK and OFDM” scheme, MBCK would operate like CCK in any suggested “Alternating Wireless Medium Access” technique aimed at achieving compatible operation between what would be “CCK/MBCK and OFDM” O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
6 9 12 18 24 36 48 54 Schematic of the SC-MBCK Option 802.11a 802.11b/MBCK 1 DSSS 2 5.5 CCK 11 22 MBCK 30 O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
Single Carrier MBCK • This is not the complete picture in the 2.4 GHz ISM Band because there is a coexistence issue caused by Bluetooth (BT) Interference which affects both • Single Carrier • Multi Carrier • 802.15.2 is addressing the coexistence issue using “Collaborative Coexistence” techniques O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
6 9 12 18 24 36 48 54 Collaborative Coexistence 802.11a 802.11b/MBCK 1 BT DSSS 2 Erase/ Mac NF/ Mac 5.5 CCK 11 22 MBCK 30 NF: Notched Filter (Deterministic frequency excision) Erase: Bit Erasures (1 MHz NF 3 erasures) MAC: AWMA/MEHTA O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
Single Carrier MBCK • In a collaborative coexistence approach SC-MBCK would use the same measures as CCK and benefit in the same way as CCK • Under the 802.15.2 recommendations SC-MBCK would be able to continue to offer high rate extensions • In the case of OFDM erasurers only at the PHY offer a limited excision of the BT interference O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
802.11a vs. Number of Erasures{R = 24Mbps - GMP Channel - SIR = 0 dB} O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
802.11a v. Number of Erasures{R = 18Mbps - GMP Channel - SIR = 0 dB} O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
Collaborative Coexistence 802.11a 802.11b/MBCK 1 6 BT DSSS 2 9 Erase/ Mac NF/ Mac 5.5 12 CCK 11 18 22 24 MBCK 30 36 Vulnerable 48 54 BT Mitigation At the PHY OFDM requires additional processing to enhance excision of the BT interference O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
SC-MBCK • SC-MBCK is a minimal extension of the single carrier concept used in 802.11b with a straight forward implementation route • Re-uses the 802.11b radio • Re-uses .11b baseband functionality • Shares a common equalisation function with CCK • No clock changes with rate adaptation • Good system performance • Offers 22 and 30 Mbps rates • Low low low complexity O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
CCK-OFDM Option 802.11a CCK-OFDM 802.11b/MBCK 1 6 6 BT DSSS 2 9 9 Erase/ Mac NF/ Mac 5.5 12 12 CCK 11 18 18 24 24 36 36 48 48 54 54 BT Mitigation Integrated Performance O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
PBCC Option 802.11a 802.11b/MBCK 1 6 BT DSSS 2 9 Erase/ Mac NF/ Mac 5.5 12 CCK 11 18 22 24 PBCC 33 36 48 54 BT Mitigation Robust Performance O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
SC-MBCK Option 802.11a 802.11b/MBCK 1 6 BT DSSS 2 9 Erase/ Mac NF/ Mac 5.5 12 CCK 11 18 22 24 MBCK 30 36 48 54 BT Mitigation Low Complexity O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
1 DATA IN 8 xI I OUT Select1 of 64Sequences 1 6 c d RSEncoder 1 xQ Q OUT 1 rI Rx I IN 1 Greatest PeakDetector Fast Correlator Bank 6 c’ y RSDecoder 1 rQ DATAOUT Rx Q IN • MBCK-RS Encoding Chain 32 Sequences + Complements 64-ary Bi-Code Keying O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
MAC 22 Mbps Base Mode 30 Mbps High Rate Mode MBCK MBCK RS(63,41) RS(63,57) MBCK Protocol Stack O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.