1. Partial Proposal: 11n Physical Layer
August 2004Month 2003
Partial Proposal: 11n Physical Layer
Michiharu Nakamura and Wladimir Bocquet
Fujitsu Laboratories Limited
Fujitsu Laboratories Ltd.

2. Summary VISA based MIMO processing PLCP frame structure
August 2004Month 2003
Summary
VISA based MIMO processing
PLCP frame structure
2 and 4 Tx antenna MIMO
Keep .11a Coding and Modulation
Reuse .11a blocks (FFT, coding, Puncturing, Interleave)
Fujitsu Laboratories Ltd.

3. Supported modes # of Rx antenna > # of Tx antenna Bit Rate (Mbps)
August 2004Month 2003
Supported modes
Bit Rate (Mbps)
Modulation
Coding Rate
# of Tx antenna 72
16QAM
3/4 2
QPSK 4 96
64QAM
2/3
1/2
108
144
192
216
# of Rx antenna > # of Tx antenna
Fujitsu Laboratories Ltd.

4. VISA Principle Basic idea VISA: VIrtual Subcarrier Assignment
August 2004Month 2003
VISA Principle
Basic idea
(a)
(b)
Power-Minimizing
Signal (a)
Zero-Amplitude Subcarrier
RLS or LMS with zero reference
Does not require
regeneration of the reference
nor synchronization
VISA: VIrtual Subcarrier Assignment
Fujitsu Laboratories Ltd.

5. Pre-FFT VISA General principle
August 2004Month 2003
Pre-FFT VISA
General principle
VISA Weight Calculation w S
FFT
Signal (a)
Signal (b)
Weights to suppress signal (b) on this subcarrier
The weights is not applicable to whole band
Because the channel is frequency dependent
(11-03/940r4)
Fujitsu Laboratories Ltd.

6. Post-FFT VISA General principle
August 2004Month 2003
Post-FFT VISA
General principle
VISA Weight Calculation w S
FFT
Signal (a)
Signal (b)
Perform Null Steering processing through all the subcarriers
Fujitsu Laboratories Ltd.

7. Proposed Frame Format 1st SP and 1st LP: Same as .11a SP and LP
August 2004Month 2003
Proposed Frame Format
SIGNAL
Ant 1
Ant 2
Ant 3
Ant 4
1st LP
2nd SP
2nd LP
1st SP
1st SP and 1st LP: Same as .11a SP and LP
SIGNAL : Same as .11a except for RATE field
2nd SP and 2nd LP (ANT 1): Same as .11a
2nd SP and 2nd LP (ANT 2,3,4) : Phase rotation of ANT1
Fujitsu Laboratories Ltd.

8. RATE Field IEEE 802.11a/g based modes Data Rate (Mbps) Modulation
August 2004Month 2003
RATE Field
IEEE a/g based modes
Data Rate (Mbps)
Modulation
Coding Rate
# of Tx
(R1,R2,R3,R4) 6
BPSK
1/2 1
1101 9
3/4
1111 12
QPSK
0101 18
0111 24
16-QAM
1001 36
1011 48
64-QAM
2/3
0001 54
0011
Fujitsu Laboratories Ltd.

9. RATE Field (cont’d) MIMO-OFDM modes Data Rate (Mbps) Modulation
August 2004Month 2003
RATE Field (cont’d)
MIMO-OFDM modes
Data Rate (Mbps)
Modulation
Coding Rate
# of Tx
(R1,R2,R3,R4) 72
16-QAM
3/4 2
0110
QPSK 4
1110 96
64-QAM
2/3
0100
1/2
1100
108
1010
144
1000
192
0010
216
0000
Fujitsu Laboratories Ltd.

10. Second Short Preamble (2nd SP)
August 2004Month 2003
Second Short Preamble (2nd SP)
SIGNAL
Ant 1
Ant 2
Ant 3
Ant 4
1st LP
2nd SP
2nd LP
1st SP
Need to perform AGC for MIMO receiver
One example is given 11-04/087r0
Codeword representation: 0 means the same polarity, 1 means the opposite polarity.
Fujitsu Laboratories Ltd.

11. Second Long Preamble (2nd LP)
August 2004Month 2003
Second Long Preamble (2nd LP)
SIGNAL
Ant 1
Ant 2
Ant 3
Ant 4
1st LP
2nd SP
2nd LP
1st SP
Antenna 1: same as .11a LP
Antenna 2: based on LP(Ant1)
Antenna 3: based on LP(Ant1)
Antenna 4: based on LP(Ant1)
Yet to find good LP configuration
Fujitsu Laboratories Ltd.

12. Channel Coding and Interleaving
August 2004Month 2003
Channel Coding and Interleaving
Keep as the Same as 11a/g coding block
SERVICE, TAIL, PAD
Scrambling, Conv. Code, Interleave
Per antenna processing / No spatial coding
PSDU
S/P
11a coding block
DATA
ANT1
ANT2
ANT3
Fujitsu Laboratories Ltd.

13. PMD function (Modulation)
August 2004Month 2003
PMD function (Modulation)
Identical to that of .11a
Fujitsu Laboratories Ltd.

14. Simulation Setup Carrier Frequency 2.4 GHz Bandwidth 20 MHz Modulation
August 2004Month 2003
Simulation Setup
Carrier Frequency
2.4 GHz
Bandwidth
20 MHz
Modulation
BPSK, QPSK, 16-QAM, 64-QAM
Channel encoder
Convolutional code
Coding rate
R=1/2 (K=7) and R=3/4 (puncturing)
Number of data subcarrier
N=48+4
Guard interval length
G=16 samples (32 for pilot symbols)
Channel model B
Channel knowledge
Estimated
Terminal speed
1 m/s
Sample period
Ts=0.05μs
(Nt,Nr)
(2,4)
Antenna spacing
Transmitter: λ , Receiver: λ/2
Fujitsu Laboratories Ltd.

15. Simulation Results Tx=2, Rx=4 with frequency domain visa processing
August 2004Month 2003
Simulation Results
Tx=2, Rx=4 with frequency domain visa processing
Fujitsu Laboratories Ltd.

16. MAC Layer Support Supported Rates element
August 2004Month 2003
MAC Layer Support
Supported Rates element
Extended Supported Rates element
Rates in 500kbps unit
Msb(bit7) to indicate BSSBasicRateSet
63.5Mbps is the maximum specifiable in current .11a/g
No designation of Antenna modes
To use pre-defined table for .11n use
Fujitsu Laboratories Ltd.

17. August 2004Month 2003
MAC Layer Support
Example of the definition of the information octet of Supported Rates element
Rate
(Mbps)
Code
Transmit Antenna Mode 1 2 18 36 72
110 4 22 44
111
5.5 11 24 48 96
112 6 12 33 66
113 9
108
114
144
115 54
192
116
216
117
Fujitsu Laboratories Ltd.

18. Thank you! For your attention. August 2004Month 2003
Fujitsu Laboratories Ltd.