Patent ID: 7904027

Claim:
A branching filter comprising: a plurality of band pass filter units, each band pass filter unit having two ports on an antenna side and one port on a radio device side for separating an outgoing wave from an incoming wave; and an antenna duplexer connected to the plurality of band pass filter units for transmitting the outgoing wave from said band pass filter units to said antenna and transmitting the incoming wave from said antenna to said band pass filter units, wherein said one port on the radio device side of each said band pass filter unit sends and receives signals to and from a radio device; wherein each said band pass filter unit includes a transmission filter for passing therethrough only a particular transmission frequency band, and a reception filter for passing therethrough only a particular reception frequency band; wherein said transmission filter and said reception filter have one terminal connected in common to form said one port on the radio device side; wherein the transmission filter of each of said plurality of band pass filters is connected to one port of the antenna duplexer, and wherein the reception filter of each of said plurality of band pass filters is connected to a second port of the antenna duplexer.