List of PPDUs Supported in 802.11e
What is a PPDU in IEEE 802.11e?
PPDU stands for Physical Protocol Data Unit, the unit of data transmitted at the PHY layer.
How does 802.11e define the PPDU structure?
It follows the basic 802.11 standard PPDU with enhancements to support QoS and power saving features.
What fields are included in an 802.11e PPDU?
It includes the preamble, SIGNAL field, service field, PSDU (MAC frame), and tail bits.
What is the role of the preamble in PPDU?
The preamble helps with synchronization, channel estimation, and signal detection at the receiver.
How does 802.11e support QoS in the PPDU?
QoS is primarily managed at the MAC layer, but 802.11e can include QoS signaling within the data carried in the PPDU.
Does 802.11e modify the modulation or coding of the PPDU?
No major changes; it supports existing modulation schemes but may prioritize QoS traffic.
What is the SIGNAL field in the PPDU?
It carries information on the data rate and length of the frame being transmitted.
How does PPDU support error detection?
Via CRC checks in the MAC frame contained within the PSDU.
Are there different PPDU formats in 802.11e?
802.11e primarily uses legacy PPDU formats but can carry QoS-enabled MAC frames.
How does 802.11e handle power saving in the PPDU transmission?
Power saving is handled at MAC but the PPDU may carry power management bits in the frame control field.
What is the PSDU in the PPDU?
The PSDU (Physical Layer Service Data Unit) carries the MAC layer frame payload.
How is the tail bits field used in PPDU?
Tail bits are used to terminate the convolutional coder in the PHY.
Can 802.11e PPDU support different data rates?
Yes, based on modulation schemes and channel conditions.
What is the relationship between PPDU and MPDU in 802.11e?
The PPDU carries the MPDU (MAC Protocol Data Unit) inside the PSDU field.
Does 802.11e introduce new PPDU types for QoS?
No new PPDU types, but it enhances QoS at the MAC and higher layers.
How does 802.11e PPDU support real-time traffic?
By carrying QoS-tagged frames that are prioritized in MAC scheduling.
Is the preamble in 802.11e different from 802.11a/b?
No significant changes; it uses the same legacy preamble.
How does 802.11e PPDU ensure synchronization?
Through the preamble and SIGNAL fields for timing and rate info.
Where can I learn more about 802.11e PPDU?
Refer to the IEEE 802.11e standard documentation and PHY/MAC layer textbooks.
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