Summary of HNS Partial Proposal for 802.11n Physical Layer doc.: IEEE 802.11-04/0abcr0 Nov 2004 Summary of HNS Partial Proposal for 802.11n Physical Layer Mustafa Eroz, Feng-Wen Sun, & Lin-Nan Lee meroz@hns.com fsun@hns.com llee@hns.com Hughes Network Systems 11717 Exploration Lane Germantown, MD 20876 Mustafa Eroz, Hughes Network Systems Mustafa Eroz, Hughes Network Systems

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

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

Nov 2004 Conclusion All the design requirements of 802.11n 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