ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS FOR WIRELESS LOCAL AREA NETWORK

摘要

A method for generating an orthogonal frequency division multiple access (OFDMA) data unit is described. A plurality of different orthogonal frequency division multiplex (OFDM) tone blocks for a wireless local area network (WLAN) communication channel are assigned to a plurality of devices including a first device and second device. The plurality of different OFDM tone blocks includes at least a first OFDM tone block assigned to the first device and a second OFDM tone block assigned to the second device. The first OFDM tone block and the second OFDM tone block together span a bandwidth equal to a smallest channel bandwidth of a legacy WLAN communication protocol. An OFDMA data unit is generated for the WLAN communication channel. The OFDMA unit includes a preamble portion and a data portion. The preamble portion has i) at least a legacy portion that spans the entire WLAN communication channel, ii) a first non-legacy portion that spans the first OFDM tone block, and iii) a second non-legacy portion that spans the second OFDM tone block.