RADIO ACCESS NETWORKS

A communication system includes a remote unit that exchanges radio frequency signals with mobile devices, at least some of the radio frequency signals comprising information destined for, or originating from, a mobile device, the remote unit being configured to perform first physical layer processing. A controller is separated from the remote unit by a switched Ethernet network, wherein data corresponding to the information is transmitted in frames between the controller and the remote unit. At least some of the data comprises baseband data that is transmitted in frequency domain. The controller and the remote unit are configured to transmit time stamp messages on the switched Ethernet network to synchronize a controller clock and a remote unit clock. The controller is configured to advance downlink subframe timing relative to the remote unit, when transmitting on the switched Ethernet network, based on a measured transport delay across the switched Ethernet network.