| 摘要 |
Provided is a band-pass filter having a small phase change in a pass band and a steep frequency characteristic. The band-pass filter includes: a four-terminal pair 90-degree hybrid circuit (10) for distributing power into two directions with a phase difference of 90 degrees; and a band elimination filter circuit including a plurality of unit circuits (15) and (16) connected to each other, each of the plurality of unit circuits including a series circuit of a coil and a capacitor and a parallel circuit of a coil and a capacitor, which are connected with each other, input terminals of the plurality of unit circuits being connected with coupling terminals (13) and (14) of the hybrid circuit (10) and output terminals of the plurality of unit circuits being terminated with resistors having impedance values equal to an output impedance.
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