| 摘要 |
A band-pass filter includes: a distributor (24) for distributing an input signal into two signals; a first low-pass filter (28) that passes a component of one of the two signals into which the input signal is distributed by the distributor (24), the component having a frequency lower than a cutoff frequency fl; a phase shifter (30) that converts a signal output from the first low-pass filter (28) so that the phase thereof is shifted by 180°; a mixer (32) that combines the other of the two signals into which the input signal is distributed by the distributor (24) with a signal output from the phase shifter (30); and a second low-pass filter (34) that passes a component of a signal output from the mixer (32), the component having a frequency lower than a second cutoff frequency f2 that is higher than the cutoff frequency fl of the first low-pass filter (28). |
