A system including a direct current tone, guard tone, data tone allocation, mapping, and inverse Fourier transform (IFT) modules. The direct current tone module determines a number of direct current tones based on whether a network device is operating in a single user or multi-user mode. The guard tone module determines a number of guard tones based on whether the network device is operating in the single user or multi-user mode. The data tone allocation module determines a number of data tones based on the number of direct current and guard tones. The mapping module receives data and based on the number of data tones, maps the data to the data tones. The IFT module performs a frequency to time domain conversion of an output of the mapping module to generate orthogonal frequency division multiplexing (OFDM) symbols during the single user mode and OFDM access symbols during the multi-user mode.