A system comprising at least one network modem configured to communicate wirelessly with at least one base station, and a subsystem configured to provide data packets to the at least one network modem to be transmitted wirelessly to the at least one base station, wherein: the at least one network modem is configured to communicate with the at least one base station using a radio frame comprising a series of subframes which divide the radio frame in time; the at least one network modem is configured to use one or more first subframes in the series of subframes for a downlink from the at least one base station; and the at least one network modem is configured to use one or more second subframes in the series of subframes for an uplink to the at least one base station.
