gsm bts rf
A combiner is a device at the base station that allows connection
of several transmitters to one antenna.there are two types of combiners hybrid and filter.hybrid combiner can combine two incoming
transmitter signals to one outgoing signal and allows all frequencies.A filter combiner allows only a
selected frequency in the transmit band to pass through.and duplexer means you can use the same antenna both uplink and downlink paths.sorry i have no metarial but if i find i would send be sure