Balanced/unbalanced filter module and communication apparatus

摘要

A balanced/unbalanced filter module includes a switch including a first port that inputs and outputs unbalanced signals in a first frequency band, a second port that inputs and outputs unbalanced signals in a second frequency band, and a third port that inputs and outputs unbalanced signals in these two frequency bands. The switch switches a signal path. An unbalanced I/O port of a first filter that passes signals in the first frequency band is connected to the port. A port of a second filter that passes signals in the second frequency band is connected to the port. Individual balanced I/O ports of each of the first and second filters are connected to first and second branch ports with substantially the same electrical length. A balance coil for impedance matching is provided between the first and second branch ports.