US Patent 8160570 Multiprotocol antenna system for multiple service provider-multiple air interface co-located base stations

A hub unit is configured to digitize first and second analog radio frequency signals in order to generate first and second digital data, respectively, indicative of the first and second analog radio frequency signals. The first and second analog radio frequency signals are broadcast from first and second base stations, respectively, associated with first and second cellular service providers, respectively, using first and second air interfaces, respectively. The first and second digital data are transported to a radio access node using a shared transport medium. The radio access node is configured to reconstruct versions of the first and second analog radio frequency signals from the first and second digital data, respectively, using first and second digital-to-analog converters and is also configured to generate first data packets from a first data radio frequency signal. The first data packets are communicated to the hub unit using the shared transport medium.