1. Summary of HNS Partial Proposal for 802.11n Physical Layer
doc.: IEEE /0abcr0
Nov 2004
Summary of HNS Partial Proposal for n Physical Layer
Mustafa Eroz, Feng-Wen Sun, & Lin-Nan Lee
Hughes Network Systems
11717 Exploration Lane
Germantown, MD 20876
Mustafa Eroz, Hughes Network Systems
Mustafa Eroz, Hughes Network Systems

2. Key Elements of the Physical Layer Proposal
Nov 2004
Key Elements of the Physical Layer Proposal
A family of high-performance FEC codes optimized for the application
Capable of decoding at information rate close to 200 Mbps with modest implementation complexity
Exceptional performance in fading channel at near 10-2 packet error rate
Flexibility to support short as well as long packets without compromise in throughput at MAC layer
MIMO/FEC integrated: no need for separated block STC
Mustafa Eroz, Hughes Network Systems

3. Nov 2004
LDPC Details
The small column weight ensures simpler decoding while performance is not sacrificed on the fading channel.
Larger block sizes are supported by simply concatenating base LDPC codes and adding one extra base block of parity check on select LDPC bits.
x x x x x x x x x x x x x
LDPC Block 1
x x x x x x x x x x x x x
LDPC Block 2
x x x x x x x x x x x x x
LDPC Block 3
Parity check on k bits : : : :
k < or = m : : : : : : : :
x x x x x x x x x x x x x
LDPC Block m
x x x x x x x x x x x x x
Parity Check Block
Mustafa Eroz, Hughes Network Systems

4. Nov 2004
Conclusion
All the design requirements of n met with the PHY partial proposal
FEC and MIMO alone achieve the goal
Extremely simple to implement
Highly efficient due to its flexible construction technique
Performance: approaching capacity for block fading and fast fading channel, performance against Channel B, D presented in September
Mustafa Eroz, Hughes Network Systems