What is TWT in WLAN 802.11ax | Target Wake Time Benefits
This page describes TWT (Target Wake Time) concept used in WLAN 802.11ax standard. It mentions benefits or advantages of TWT (Target Wake Time) which increases battery life.
IEEE 802.11ax standard is the evolution of legacy 802.11 wifi standards such as 802.11a/g/n/ac. Previous standards have been developed mainly to focus on increasing raw data rates. 802.11ax has been developed to address issues faced in the previous standards as well as to add new advanced features. 802.11ax focuses on better efficiency, capacity and performance. TWT is one of the new features introduced to increase battery life.
What is TWT (Target Wake Time) in 802.11ax ?
OFDM symbol is longer in 802.11ax which is about 12.8 µs duration. There are three guard interval options viz. 0.8, 1.6 or 3.2 µs. The figure-1 depicts 802.11ax frame with AP and two client devices with wakeup and sleep times.
As shown it uses predefined uplink access. Wifi devices need not have to contend for uplink access. During the period when there is no transmissions wifi users will sleep and when they have transmissions they will wake up.
Benefits or Advantages of TWT in 802.11ax
➨It reduces power consumption by adopting sleep time. Hence battery life is increased.
➨It minimizes contention among stations by adopting scheduled uplink access. As there is no contention, congestion among stations can be minimized to a great extent.
WLAN 802.11ac and 802.11ax related links
WLAN 802.11ax tutorial
advantages and disadvantages of 802.11ac
advantages and disadvantages of 802.11ax
Difference between 802.11ac Wave1 and Wave2
Difference between 802.11n,11ac,11ad
WLAN 802.11ac tutorial
WLAN 802.11ac frame structure
WLAN 802.11ac Physical Layer
802.11ac MAC Layer
WLAN 11a,11b,11n,11ac frame structures