BRANCHING FILTER AND COMMUNICATION MODULE

摘要

A branching filter (1) comprises: an antenna terminal (3) that receives signal waves and disturbance waves; a transmission filter (11) that is connected to the antenna terminal (3); a reception filter (13) that is connected to the antenna terminal (3) and receives some of the signal waves and that has, as passband, a frequency range higher than the passband of the transmission filter (11); and a disturbance wave resonator (15) that is connected to the antenna terminal (3) and also to the ground and positioned closer to the antenna terminal (3) than the transmission filter (11) and the reception filter (13). The disturbance wave resonator (15) is connected to the antenna terminal (3) in such a manner that the disturbance wave resonator (15) is positioned closer to the antenna terminal (3) than the transmission filter (11) and also closer to the antenna terminal (3) than the reception filter (13). The resonance frequency of the disturbance wave resonator (15) is of a frequency range that is smaller than the passband of the transmission filter and that includes the frequency range of the disturbance waves.