802.11bn Physical Rates ========================= .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the maximum physical data rate in 802.11bn?** The maximum theoretical PHY rate is 600 Mbps using 4 spatial streams, 40 MHz channel bandwidth, and short guard interval, while maintaining backward compatibility. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What legacy physical rates are supported in 802.11b?** 1, 2, 5.5, and 11 Mbps using DSSS and CCK modulation in 2.4 GHz band. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How does 802.11bn support backward compatibility with 802.11b devices?** By using Mixed Mode preambles and including legacy fields, it allows coexistence but reduces maximum throughput. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can 802.11bn devices fall back to 802.11b physical rates?** Yes, devices automatically fall back to legacy rates to maintain compatibility with b-only clients. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the impact of 802.11b clients on 802.11bn network throughput?** The presence of 802.11b clients slows the entire network due to longer preambles and slower transmission rates. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What channel bandwidths are supported in 802.11bn?** Both 20 MHz and 40 MHz channel widths are supported, but 40 MHz is less common in mixed mode due to interference concerns. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How many spatial streams are supported in 802.11bn?** Up to 4 spatial streams like 802.11n, but real-world deployments often use fewer. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What modulation schemes does 802.11bn use for 802.11n packets?** OFDM with BPSK, QPSK, 16-QAM, and 64-QAM depending on MCS index and channel conditions. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What modulation does 802.11b use?** DSSS with DBPSK and DQPSK for 1 and 2 Mbps; CCK for 5.5 and 11 Mbps. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How does the guard interval affect physical rates in 802.11bn?** Using short guard interval (400 ns) boosts PHY rates by approximately 10%, but it is sometimes disabled for compatibility. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are MCS indexes used in 802.11bn?** Yes, MCS indexes define modulation, coding rate, spatial streams, and guard intervals for the 802.11n portion. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the lowest physical rate in 802.11bn?** 1 Mbps from 802.11b legacy rates. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does 802.11bn support channel bonding?** Yes, 40 MHz channel bonding is supported but may be limited in mixed environments due to legacy interference. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How is the physical rate selected in 802.11bn?** Devices adaptively select the highest possible rate based on signal quality, supported MCS, and coexistence requirements. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What effect does the presence of 802.11b devices have on short guard interval usage?** It may force the network to use a longer guard interval to maintain compatibility, reducing peak PHY rates. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How do 802.11bn devices handle collisions with 802.11b clients?** Mixed mode uses protection mechanisms like RTS/CTS to minimize collisions and maintain throughput. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the typical real-world maximum throughput for 802.11bn?** Usually around 100–200 Mbps due to overhead and legacy client presence. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are there any interoperability issues with 802.11bn physical rates?** Sometimes, older 802.11b devices can cause network slowdown and increase latency. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can 802.11bn achieve the same rates as pure 802.11n networks?** No, due to legacy device overhead and protection mechanisms, maximum rates are generally lower. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow Topics in this section, * :ref:`physical_rates in 802.11bn ` * :ref:`Reference links ` .. tab-set:: .. tab-item:: physical_rates in 802.11bn =========== ==== ==== =========== ============ =========== ================ ========= ============ =========== ========== =========== Modulation BW Tsc FSP=BW/Tsc Tdata=1/FSP GI (ns) Symbol (ns) 1/Symbol Bits/Symbol Code rate Usable sc Rate (Mbps) =========== ==== ==== =========== ============ =========== ================ ========= ============ =========== ========== =========== BPSK 20 256 78.125 12.8 800 13.6 0.0735 1 1/2 234 7.8 BPSK 20 256 78.125 12.8 400 13.2 0.0758 1 3/4 234 11.7 QPSK 20 256 78.125 12.8 800 13.6 0.0735 2 1/2 234 15.6 QPSK 20 256 78.125 12.8 400 13.2 0.0758 2 3/4 234 23.4 16-QAM 20 256 78.125 12.8 800 13.6 0.0735 4 1/2 234 31.2 16-QAM 20 256 78.125 12.8 400 13.2 0.0758 4 3/4 234 46.8 64-QAM 20 256 78.125 12.8 800 13.6 0.0735 6 2/3 234 41.6 64-QAM 20 256 78.125 12.8 400 13.2 0.0758 6 3/4 234 46.8 256-QAM 20 256 78.125 12.8 800 13.6 0.0735 8 3/4 234 62.4 256-QAM 20 256 78.125 12.8 400 13.2 0.0758 8 5/6 234 78.0 1024-QAM 20 256 78.125 12.8 800 13.6 0.0735 10 3/4 234 78.0 1024-QAM 20 256 78.125 12.8 400 13.2 0.0758 10 5/6 234 97.5 4096-QAM 20 256 78.125 12.8 800 13.6 0.0735 12 3/4 234 93.6 4096-QAM 20 256 78.125 12.8 400 13.2 0.0758 12 5/6 234 117.0 BPSK 40 512 78.125 12.8 800 13.6 0.0735 1 1/2 468 15.6 BPSK 40 512 78.125 12.8 400 13.2 0.0758 1 3/4 468 23.4 QPSK 40 512 78.125 12.8 800 13.6 0.0735 2 1/2 468 31.2 QPSK 40 512 78.125 12.8 400 13.2 0.0758 2 3/4 468 46.8 16-QAM 40 512 78.125 12.8 800 13.6 0.0735 4 1/2 468 62.4 16-QAM 40 512 78.125 12.8 400 13.2 0.0758 4 3/4 468 93.6 64-QAM 40 512 78.125 12.8 800 13.6 0.0735 6 2/3 468 83.2 64-QAM 40 512 78.125 12.8 400 13.2 0.0758 6 3/4 468 93.6 256-QAM 40 512 78.125 12.8 800 13.6 0.0735 8 3/4 468 124.8 256-QAM 40 512 78.125 12.8 400 13.2 0.0758 8 5/6 468 156.0 1024-QAM 40 512 78.125 12.8 800 13.6 0.0735 10 3/4 468 156.0 1024-QAM 40 512 78.125 12.8 400 13.2 0.0758 10 5/6 468 195.0 4096-QAM 40 512 78.125 12.8 800 13.6 0.0735 12 3/4 468 187.2 4096-QAM 40 512 78.125 12.8 400 13.2 0.0758 12 5/6 468 234.0 BPSK 80 1024 78.125 12.8 800 13.6 0.0735 1 1/2 980 32.7 BPSK 80 1024 78.125 12.8 400 13.2 0.0758 1 3/4 980 49.1 QPSK 80 1024 78.125 12.8 800 13.6 0.0735 2 1/2 980 65.4 QPSK 80 1024 78.125 12.8 400 13.2 0.0758 2 3/4 980 98.1 16-QAM 80 1024 78.125 12.8 800 13.6 0.0735 4 1/2 980 130.8 16-QAM 80 1024 78.125 12.8 400 13.2 0.0758 4 3/4 980 196.2 64-QAM 80 1024 78.125 12.8 800 13.6 0.0735 6 2/3 980 174.5 64-QAM 80 1024 78.125 12.8 400 13.2 0.0758 6 3/4 980 196.2 256-QAM 80 1024 78.125 12.8 800 13.6 0.0735 8 3/4 980 261.6 256-QAM 80 1024 78.125 12.8 400 13.2 0.0758 8 5/6 980 326.9 1024-QAM 80 1024 78.125 12.8 800 13.6 0.0735 10 3/4 980 326.9 1024-QAM 80 1024 78.125 12.8 400 13.2 0.0758 10 5/6 980 408.6 4096-QAM 80 1024 78.125 12.8 800 13.6 0.0735 12 3/4 980 374.4 4096-QAM 80 1024 78.125 12.8 400 13.2 0.0758 12 5/6 980 468.0 BPSK 160 2048 78.125 12.8 800 13.6 0.0735 1 1/2 1960 65.4 BPSK 160 2048 78.125 12.8 400 13.2 0.0758 1 3/4 1960 98.1 QPSK 160 2048 78.125 12.8 800 13.6 0.0735 2 1/2 1960 130.8 QPSK 160 2048 78.125 12.8 400 13.2 0.0758 2 3/4 1960 196.2 16-QAM 160 2048 78.125 12.8 800 13.6 0.0735 4 1/2 1960 261.6 16-QAM 160 2048 78.125 12.8 400 13.2 0.0758 4 3/4 1960 392.4 64-QAM 160 2048 78.125 12.8 800 13.6 0.0735 6 2/3 1960 349.0 64-QAM 160 2048 78.125 12.8 400 13.2 0.0758 6 3/4 1960 392.4 256-QAM 160 2048 78.125 12.8 800 13.6 0.0735 8 3/4 1960 523.2 256-QAM 160 2048 78.125 12.8 400 13.2 0.0758 8 5/6 1960 653.8 1024-QAM 160 2048 78.125 12.8 800 13.6 0.0735 10 3/4 1960 653.8 1024-QAM 160 2048 78.125 12.8 400 13.2 0.0758 10 5/6 1960 817.2 4096-QAM 160 2048 78.125 12.8 800 13.6 0.0735 12 3/4 1960 748.8 4096-QAM 160 2048 78.125 12.8 400 13.2 0.0758 12 5/6 1960 937.5 BPSK 320 4096 78.125 12.8 800 13.6 0.0735 1 1/2 3920 130.8 BPSK 320 4096 78.125 12.8 400 13.2 0.0758 1 3/4 3920 196.2 QPSK 320 4096 78.125 12.8 800 13.6 0.0735 2 1/2 3920 261.6 QPSK 320 4096 78.125 12.8 400 13.2 0.0758 2 3/4 3920 392.4 16-QAM 320 4096 78.125 12.8 800 13.6 0.0735 4 1/2 3920 523.2 16-QAM 320 4096 78.125 12.8 400 13.2 0.0758 4 3/4 3920 784.8 64-QAM 320 4096 78.125 12.8 800 13.6 0.0735 6 2/3 3920 698.0 64-QAM 320 4096 78.125 12.8 400 13.2 0.0758 6 3/4 3920 784.8 256-QAM 320 4096 78.125 12.8 800 13.6 0.0735 8 3/4 3920 1046.4 256-QAM 320 4096 78.125 12.8 400 13.2 0.0758 8 5/6 3920 1307.6 1024-QAM 320 4096 78.125 12.8 800 13.6 0.0735 10 3/4 3920 1307.6 1024-QAM 320 4096 78.125 12.8 400 13.2 0.0758 10 5/6 3920 1634.4 4096-QAM 320 4096 78.125 12.8 800 13.6 0.0735 12 3/4 3920 1497.6 4096-QAM 320 4096 78.125 12.8 400 13.2 0.0758 12 5/6 3920 1875.0 =========== ==== ==== =========== ============ =========== ================ ========= ============ =========== ========== =========== .. _physical_rates_step17: .. tab-set:: .. tab-item:: Reference links * Reference links