Systems and methods for orthogonal frequency division multiplexing are provided. In one embodiment, a method for ranging comprises: receiving at a host a plurality of upstream symbols transmitted from a plurality of remote units, the upstream symbols transmitted on a plurality of orthogonal carriers modulated using an inverse Fourier transform; comparing a phase of at least one ranging symbol received from at least one of the plurality of remote units with a phase of a symbol transmitted by the host; and transmitting an adjustment instruction instructing the at least one of the plurality of remote units to vary a phase of transmissions transmitted from the at least one of the plurality of remote units based on a difference in phase between the at least one ranging symbol and the symbol transmitted by the host unit.