An optical line terminal (OLT) comprising a receiver configured to couple to a mode coupler via a multi-mode optical fiber that supports more than one optical communication mode, and couple to a plurality of optical network units (ONUs) via the mode coupler, a processor coupled to the receiver and configured to schedule upstream multi-mode transmissions from the ONUs via the multi-mode fiber and the mode coupler by employing time division multiplexing (TDM), and a transmitter coupled to the processor and configured to transmit schedule data to the ONUs.