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How Does DL-OFDMA Work in 802.11ax?

You should always remember that multi-user OFDMA communication is only for 802.11 data frame exchanges between an 802.11ax AP and multiple 802.11ax clients. For backward compatibility, management and control frames will still be sent using single-user OFDM. In a previous blog, we mentioned that a series of frame exchanges are used for both DL-OFDMA and […]

What are OFDMA Trigger Frames?

In previous blogs, you have learned that an 802.11ax access point uses OFDMA technology to partition a channel into smaller sub-channels called resource units (RUs) so that simultaneous multiple-user transmissions can occur. The AP mandates the RU allocation of a 20 MHz for multiple clients for both downlink and uplink OFDMA. When referencing downlink and uplink OFDMA […]

OFDM and OFDMA Subcarriers – What Are the Differences?

As we continue our 802.11ax blog series, let’s discuss both OFDM and OFDMA technologies used for Wi-Fi communications. 802.11a/g/n/ac radios currently use Orthogonal Frequency Division Multiplexing (OFDM) for single-user transmissions on an 802.11 frequency. 802.11ax radios can utilize Orthogonal frequency-division multiple access (OFDMA) which is a multi-user version of the OFDM digital-modulation technology. OFDMA subdivides a channel […]

How Does an 802.11ax AP Allocate OFDMA Resource Units?

In the previous blog, you learned that 802.11ax access point uses OFDMA technology to partition a channel into smaller sub-channels called resource units (RUs) so that simultaneous multiple-user transmissions can occur. The AP mandates the RU allocation of a 20 MHz for multiple clients for both downlink and uplink OFDMA. RU allocation information is communicated to […]

What are OFDMA Resource Units in 802.11ax?

In our last 802.11ax blog, we discussed how OFDMA is the main 802.11ax enhancement that offers the biggest bang for the buck. Orthogonal frequency-division multiple access (OFDMA) is a multi-user version of OFDM digital-modulation technology. OFDMA subdivides a channel into smaller frequency allocations. By subdividing the channel, parallel transmissions of small frames to multiple clients can […]

The Main Ingredient of 802.11ax: OFDMA

In previous blogs, we have discussed many 802.11ax PHY and MAC enhancements including BSS color, spatial reuse, Multi-TID AMPDU, 20 MHz-only clients and more. However, we have not yet dedicated a lot of blog discussion about the main 802.11ax enhancement that offers the biggest bang for the buck: OFDMA. 802.11a/g/n/ac radios currently use Orthogonal Frequency […]