802.11ba – the one that slept with one eye open

802.11ba isn’t about speed, range, or streaming. it’s about **not wasting power**. also known as **Wake-up Radio (WUR)**, this amendment was designed for devices that don’t need constant Wi-Fi – but still want to stay connected... kinda.

published in 2021 and part of IEEE 802.11-2020, 802.11ba added a **secondary ultra-low-power radio path**. think of it as a mini-listener that only wakes the main Wi-Fi chip when something actually matters.

who’s it for? mostly low-power or battery-sensitive devices like IoT sensors, smart locks, wearables, or anything that shouldn’t burn through juice just by listening to beacons all day.

tech highlights:

  • WUR PHY: defines a new Wake-up PHY layer, optimized for **super low power** listening
  • Wake-up Frames: special frames with WUR-specific structure – not your average 802.11 traffic
  • Dual radio paths: main radio sleeps → WUR PHY stays alert for valid triggers → main radio wakes if needed
  • Security: yes, wake-up frames can be authenticated – no rogue alarms here
  • Use cases: IoT, low-duty-cycle devices, smart home gear, maybe even industrial monitoring systems

802.11ba doesn't make Wi-Fi faster. it makes it **smarter and more efficient** for things that just want to sip battery. and it's fully part of the IEEE 802.11-2020 core.

802.11ba gave Wi-Fi a quiet mode. a low-power ear to the world. perfect for devices that wanna sleep, but not miss the important stuff.