US Patent 11039440 OFDMA with block tone assignment for WLAN

An access point (AP) device assigns respective blocks of orthogonal frequency division multiplexing (OFDM) tones to a plurality of client stations for an orthogonal frequency division multiple access (OFDMA) data unit. The AP device receives respective independent data for the plurality of client stations, and generates a preamble of the OFDMA data unit to include: respective legacy preamble portions in respective sub-channels. Each legacy preamble portion includes a legacy signal field that indicates a duration of the OFDMA data unit, and a non-legacy preamble portion. The AP device also generates a data portion of the OFDMA data unit to include respective independent data for respective client stations. The respective independent data are included within the respective blocks of OFDM tones.