In exemplary embodiments, the optional clock unit 216 extracts the master reference clock from the downlink signal and uses this master clock within the remote unit 104 to establish a common time base in the remote unit 104 with the rest of the distributed antenna system 100. In exemplary embodiments, the optional clock unit 216 generates a master reference clock and distributes the generated master reference clock to other components of the distributed antenna system 100 (and even the external devices 110) in the upstream using the uplink signal.