At least one example embodiment discloses a system including a processor configured to receive a plurality of upstream pilot signals from a plurality of remote transceivers, respectively, in a time domain, determine channel coefficients based on the plurality of upstream pilot signals, determine filter coefficients based on the channel coefficients and to control transmission of the upstream pilot signals in the time domain to physical layers of a plurality of processing devices, the plurality of processing devices configured to communicate with the plurality of remote transceivers through the processor.