1. Hervé Bonneville, Bruno Jechoux, Romain Rollet
Month 2003
doc.: IEEE /xxxr0
MITMOT “Mac and mImo Techniques for MOre Throughput” alliance proposal presentation in response to IEEE802.11n CFP
Hervé Bonneville, Bruno Jechoux, Romain Rollet
Mitsubishi ITE 1, allee de Beaulieu, Rennes, France
Markus Muck, Marc de Courville, Jean-Noël Patillon, Stéphanie Rouquette-Léveil, Alexandre Ribeiro Dias, Karine Gosse, Brian Classon, Keith Blankenship
Motorola Labs
Parc les Algorithmes – Saint Aubin – Gif sur Yvette Cedex - France E. Algonquin Rd, Schaumburg, IL , USA
Jechoux,Patillon Mitsubishi/Motorola
H.Bonneville, B.Jechoux, Mitsubishi ITE

2. Overall goal and positioning
Preserve compatibility with legacy IEEE system
Evolution: expand current WLAN application domain, offer a consistent solution to
Provide required QoS to support consumer electronics (multimedia home environment and VoIP enterprise)
Grant range extension for limited outdoor operation (hotspot) as well as full home coverage
Support heterogeneous traffic: increase overall peak data rate without jeopardizing lower data rates modes
Manage diversity (laptop/PDA/VoIP Phone) and evolution (independent STA/AP antenna configuration upgrade) of devices through asymmetric antenna configurations
Proven and simple solution: combine a highly efficient contention-free based MAC with robust yet low complexity open-loop MIMO PHY techniques
Jechoux,Patillon Mitsubishi/Motorola

3. .11n MAC: an evolutionary approach
Month 2003
doc.: IEEE /xxxr0
.11n MAC: an evolutionary approach
Solutions:
Centralised on demand resource allocation with grouped resource announcements,
embedded in .11e superframe
providing contention free access for all type of .11n traffics
Aggregated PHY bursts made of short fixed size MAC-PDUs
allows 1 or multiple destinations and/or PHY modes
Enhanced ACK: low latency and low overhead selective retransmission
Benefits:
Actual QoS: guaranteed throughput, stringent delay constraints support
even in heavily loaded system
High efficiency and scalable architecture
scenario SS16 (point to point): 86% - extended SS6 (Hotspot): 67%
maintain constant overhead when data rate increases
Efficient for heterogeneous traffics (bursty, VBR, CBR, high or low data rates)
without parameter tuning
Easy implementation, low power consumption
summary deck
Jechoux,Patillon Mitsubishi/Motorola
H.Bonneville, B.Jechoux, Mitsubishi ITE

4. .11n PHY: a MIMO robust extension
Goal: define new OFDM MIMO modes with the constraints to
handle asymmetric TX/RX antenna configurations with 1, 2 or 3 parallel streams
focus on open-loop for stability, avoiding calibration circuit or feedback signalling
Solution: exploit a hybrid combination of
Spatial Division Multiplexing (SDM) to increase spectrum efficiency and peak data rates
classical Space Time Block Coding (STBC) to improve link robustness or range for low to medium data rates (suited to small packet size e.g. VoIP)
Additional key features:
mandatory: 20MHz bandwidth, minimum of 2Tx antennas (up to 4Tx)
new two stage space and frequency interleaver design
Forward Error Correction scheme:
supports all .11a CC rates, adds low redundancy 5/6 (mandatory)
advanced optional scheme: binary turbo code derived from 3GPP
second 20MHz/128 carriers OFDM modulation (8% rate increase), with double duration guard interval (Hotspot: limited outdoor)
optional high rate 40MHz bandwidth/128 carriers modes (117% rate gain)
new nPLCP preambles: code overlay STS/orthogonal LTS
Jechoux,Patillon Mitsubishi/Motorola

5. Differentiators Resource allocation mechanism is highly dynamic
QoS provided without use of traffic profiles (TSPECS)
Enhanced transparency and predictability through broadcast grouped resource announcement
yields clean low power implementation and low overhead
Inherent clean split between legacy and .11n devices at MAC level
no need for mixed-modes transmission mode definition
High Efficiency independent of application packet size through segmentation
Robustness to error through retransmission mechanism on segmented packets
.11n specific beacon enables materialization of new PHY mode range prediction
Build in support for asymmetric TX/RX antenna configurations to accommodate various terminal sizes (PDA/Phone) offering a scalable and evolutionary solution
New preamble definition: allowing simple yet accurate AGC, time synchronization and easier quality/complexity tradeoff for CSI estimation
Open-loop link quality feedback for easier and better link adaptation
Jechoux,Patillon Mitsubishi/Motorola