Power Saving Mechanisms in IEEE 802.11aj
What power saving mechanisms are defined in 802.11aj?
802.11aj includes power saving features adapted for directional 45 GHz and 60 GHz bands to reduce device energy consumption.
How does 802.11aj handle sleep modes for stations?
Stations can enter low-power sleep states coordinated with scheduled wake-up periods aligned to Service Periods.
What role does the PCP play in power saving?
The PCP schedules Service Periods and Contention-Based Access Periods, helping stations optimize active and sleep durations.
Does 802.11aj support power save polling?
Yes, stations use PS-Poll frames to request buffered data from the PCP during awake intervals.
How does directional communication affect power saving?
Directional beams focus energy and reduce interference, enabling efficient power usage during transmissions.
Are there mechanisms for adaptive power saving in 802.11aj?
Yes, power saving is adapted dynamically based on traffic demand and channel conditions.
How are wake-up schedules managed in 802.11aj?
Wake-up times are coordinated with Service Period schedules broadcast by the PCP to minimize idle listening.
What is the impact of multi-band operation on power saving?
802.11aj coordinates power saving across 45 GHz and 60 GHz bands, allowing devices to sleep on unused bands.
Does 802.11aj support power saving in mesh networks?
Yes, mesh stations can apply power save strategies while maintaining mesh connectivity and routing.
How does beamforming influence power consumption?
Beamforming reduces transmission power needs by focusing signals, lowering overall device energy use.
Are there power saving mechanisms for beacon transmissions?
Beacons are transmitted efficiently with scheduled intervals, and stations wake up only when necessary to listen.
How does 802.11aj handle buffering of frames during sleep?
PCP buffers downlink frames for sleeping stations, delivering them upon station wake-up requests.
What role do Service Periods play in power saving?
Service Periods allow scheduled data exchange reducing idle listening and allowing stations to sleep outside these intervals.
Is there support for power save with contention-based access?
Yes, stations may wake during contention periods if they have urgent data to send or receive.
How do stations signal their power save state?
Stations indicate their power save mode using specific MAC control frames and flags.
Can 802.11aj devices enter deep sleep modes?
Yes, devices can enter deeper sleep modes with longer wake-up intervals to save more energy.
How does power saving affect latency in 802.11aj?
There is a trade-off: aggressive power saving increases latency due to longer sleep intervals but saves energy.
Are there any enhancements to legacy power saving features in 802.11aj?
Yes, enhancements accommodate directional antennas, multi-band use, and the unique characteristics of mmWave frequencies.
How do power saving mechanisms in 802.11aj benefit mobile devices?
By reducing active radio time and optimizing beamforming, 802.11aj extends battery life in mobile and IoT devices.
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