Systems and methods for synchronization techniques in multipoint-to-point
communication using orthogonal frequency division multiplexing are
provided. In one embodiment, a method for multipoint-to-point
communication 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; and determining respective round trip path
delay values associated with each of at least two of the plurality of
remote units.