Power Saving Mechanisms in IEEE 802.11ax protocol

What power saving mechanisms are introduced in IEEE 802.11ax?

802.11ax introduces Target Wake Time (TWT) and enhanced Power Save Mode (PSM) to reduce energy consumption.

How does Target Wake Time (TWT) improve power saving?

TWT schedules specific wake times for devices, allowing them to sleep longer and reduce idle listening.

What is the difference between individual and broadcast TWT?

Individual TWT is negotiated between AP and a single client; broadcast TWT schedules wake times for multiple clients.

Does 802.11ax support legacy power save methods?

Yes, it supports traditional Power Save Mode (PSM) for backward compatibility.

How does TWT reduce contention and improve efficiency?

By scheduling transmissions, TWT minimizes simultaneous wake-ups and channel contention among devices.

Can TWT be used in uplink and downlink transmissions?

Yes, TWT schedules wake times for both uplink and downlink data transmissions.

How does 802.11ax support power saving in multi-user scenarios?

It uses TWT along with OFDMA and MU-MIMO to efficiently schedule multi-user transmissions and reduce device active time.

What role does the AP play in power saving for 802.11ax?

The AP coordinates TWT schedules and buffers data during client sleep periods to optimize battery life.

Does 802.11ax improve power saving for IoT devices?

Yes, TWT and scheduled access reduce power consumption, ideal for battery-operated IoT devices.

How does 802.11ax handle broadcast and multicast traffic in power saving?

Broadcast and multicast frames are delivered during scheduled Delivery Traffic Indication Map (DTIM) intervals.

Can devices wake up on-demand outside scheduled TWT?

Yes, devices can request unscheduled service but it may reduce power savings.

How does 802.11ax power saving differ from 802.11ac?

802.11ax adds TWT and more efficient multi-user scheduling compared to the basic PSM in 802.11ac.

Are there new power save states in 802.11ax?

Yes, devices can enter longer sleep periods coordinated via TWT for better battery life.

Does 802.11ax support negotiation of multiple TWT schedules?

Yes, clients can negotiate multiple TWT agreements to optimize different traffic flows.

How does power saving affect latency in 802.11ax?

Scheduled wake times may increase latency but balance power efficiency with timely data delivery.

Can TWT schedules be dynamically updated?

Yes, TWT agreements can be modified based on changing traffic or device requirements.

Is power saving in 802.11ax compatible with all client devices?

Older devices may not support TWT but can still use legacy power save modes.

How does power saving impact overall network throughput?

Efficient scheduling reduces contention, potentially improving throughput while saving power.

Where can I learn more about 802.11ax power saving?

IEEE 802.11ax standard documents and Wi-Fi Alliance technical whitepapers provide detailed insights.

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