In an aspect, an apparatus for distribution of frequency reference to a receiving end over a transmission medium comprises a first mixer adapted to mix a frequency reference signal having a reference frequency with a local oscillator signal having a local oscillator frequency to provide a forward frequency reference signal, a communication section adapted to transmit the forward frequency reference signal and receive a first backward frequency reference signal, a second mixer adapted to mix the first backward frequency reference signal with the local oscillator signal to provide a second backward frequency reference signal and a phase comparator and control circuit adapted to adjust the local oscillator frequency based on a phase shift of the second backward frequency reference signal so as to compensate for a phase shift of the forward frequency reference signal.