List of PPDUs Supported in 802.11ax 6E ======================================== .. 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 a PPDU in the context of IEEE 802.11ax 6E?** PPDU stands for Physical Protocol Data Unit, the complete unit of data that is transmitted over the wireless medium, including preamble and payload. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How many types of PPDUs are supported in 802.11ax 6E?** There are five types: HE SU PPDU, HE MU PPDU, HE ER SU PPDU, HE TB PPDU, and HE Extended Range PPDU. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is an HE SU PPDU?** HE SU (High Efficiency Single User) PPDU is used for single-user transmission and is backward compatible with 802.11a/n/ac devices. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is HE MU PPDU used for?** HE MU (Multi-User) PPDU is used for simultaneous transmission to multiple users using OFDMA and/or MU-MIMO techniques. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the purpose of HE TB PPDU?** HE TB (Trigger-Based) PPDU supports uplink transmissions that are initiated by the AP using trigger frames, enabling scheduled access. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is HE ER SU PPDU?** HE ER SU (Extended Range Single User) PPDU is designed for longer-range communication in the 2.4 GHz and 5 GHz bands, especially useful for IoT. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Which PPDU types support uplink transmissions?** HE TB PPDU and HE MU PPDU support uplink transmissions from clients to the AP. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Which PPDU types are exclusive to 802.11ax (Wi-Fi 6/6E)?** All five PPDU types—HE SU, HE MU, HE TB, HE ER SU, and HE Extended Range—are new in 802.11ax and not available in legacy standards. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can legacy devices interpret HE PPDUs?** No. Legacy devices cannot decode HE-specific PPDUs, but 802.11ax APs maintain interoperability through compatible preambles and fallbacks. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Do 6 GHz transmissions use a different PPDU format?** No new PPDU type is introduced for 6 GHz, but HE PPDUs are optimized for the cleaner, wider channels available in this band. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Is there a difference in preamble structure between HE PPDUs?** Yes, each PPDU type has a slightly different preamble tailored to its use case (e.g., SU, MU, TB), though all start with an L-STF/L-LTF for legacy compatibility. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the benefit of using HE MU PPDU over HE SU PPDU?** HE MU PPDU allows efficient utilization of the spectrum by serving multiple users simultaneously, improving throughput and efficiency. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What are the key enhancements in HE TB PPDU for uplink efficiency?** It enables scheduled access, reduces collisions, and supports low-latency, high-efficiency transmission for uplink traffic. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are HE PPDUs compatible across 2.4 GHz, 5 GHz, and 6 GHz bands?** Yes, HE PPDUs are designed to be band-agnostic and operate across all three frequency bands supported by Wi-Fi 6E. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What’s the role of L-SIG in HE PPDU formats?** The L-SIG (Legacy Signal field) is included for compatibility with older devices and to allow carrier sensing. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How are PPDU durations calculated in 802.11ax?** PPDU duration depends on modulation, coding scheme (MCS), guard interval (GI), and number of spatial streams, among other factors. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Do all PPDU types support the same Modulation and Coding Schemes (MCS)?** Most HE PPDUs support up to MCS 11, but support may vary by device and band. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the maximum channel width supported by HE PPDUs in Wi-Fi 6E?** In the 6 GHz band, HE PPDUs can operate over channel widths up to 160 MHz, or 320 MHz with Wi-Fi 7 (not in 802.11ax). .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How do PPDU formats influence power consumption?** Shorter, more efficient PPDUs like those in trigger-based transmissions reduce airtime and power usage for battery-powered devices. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are custom or vendor-specific PPDUs allowed?** No, all PPDU formats must conform to the IEEE 802.11ax standard to ensure interoperability across devices and vendors. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow Topics in this section, * :ref:`Reference links ` .. _ppdu6e_step17: .. tab-set:: .. tab-item:: Reference links * Reference links