A first communication device receives, from a second communication device, a synchronization frame having an allocation indicator that indicates a non-overlapping allocation of pilot tones. The first communication device generates a first data frame that comprises a plurality of orthogonal frequency division multiplexing (OFDM) symbols of a non-legacy training field portion, the plurality of OFDM symbols including only pilot tones corresponding to the non-overlapping allocation of pilot tones. The first communication device transmits, in response to the synchronization frame and via a multiple input, multiple output (MIMO) communication channel, the first data frame to the second communication device simultaneously with a transmission of a second data frame by a third communication device via the MIMO communication channel, wherein corresponding OFDM symbols of respective non-legacy training field portions of the first data frame and the second data frame include non-overlapping pilot tones according to the non-overlapping allocation.