TRANSMIT NETWORK FOR A CELULAR BASE-STATION.

摘要

A TRANSMIT NETWORK FOR CELLULAR MOBILE RADIO NETWORKS INCORPORATES TWO TRANSMIT MULTIPLEXERS 122ABE AND 122CD: THE FIRST TRANSMIT MULTIPLEXER 122ABE RECEIVES A GROUP OF OUTPUT SIGNALS FROM THREE TRANSMITTERS 124A, 124B AND 124E, AND FILTERS THEM IN RESPECTIVE BAND-PASS FILTERS 126A, 126B AND 126E; THE SECOND TRANSMIT MULTIPLEXER 122CD RECEIVES A GROUP OF OUTPUT SIGNALS FROM TWO FURTHER TRANSMITTERS 124C AND 124D, AND FILTERS THEM IN RESPECTIVE BAND-PASS FILTERS 126C AND 126D. THE TRANSMIT FREQUENCIES IN EACH SIGNAL GROUP ARE NON-ADJACENT, WHICH IMPROVES ISOLATION BETWEEN TRANSMITTERS PROVIDED BY THE FILTERS 126. FILTERED OUTPUT SIGNALS FROM RESPECTIVE BAND-PASS FILTERS 126 ARE COMBINED AT FILTER OUTPUTS 128X AND 128Y FROM WHICH SIGNALS ARE COMBINED IN A COMBINER 132 PROVIDING A DEGREE OF ISOLATION BETWEEN THESE OUTPUTS AND ENABLING THE SIGNALS TO BE COMBINED WITH MINIMAL DISTORTION. SIGNALS FROM THE COMBINER 132 ARE FED VIA A DUPLEXER TO A TRANSMIT/RECEIVE ANTENNA.(FIG 12)