| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a polyphase filter with a small variation in phase difference and amplitude between four output signals obtained from an output terminal, due to a length difference in interconnections for connecting resisters and capacitors. Ž<P>SOLUTION: Eight sets of series circuit in which resisters and capacitors are series-connected are sequentially connected to configure a bridge circuit for outputting and distributing input signals from its output terminal to a signal with a phase difference of 90 degrees and an equal amplitude. Connection points between the resisters and capacitors of the series circuits are defined as first to eighth input terminals 30a to 30h. Connection points between the eight sets of series circuit are defined as first to eighth output terminals 40a to 40h. The first and second input terminals adjacent to each other and the fifth and sixth output terminals adjacent to each other are connected and a positive-phase high-frequency differential signal is supplied to the first and third input terminals 31a, 31c, while third and fourth input terminals adjacent to each other and the seventh and eighth output terminals adjacent to each other are connected and a reverse-phase high-frequency differential signal is supplied to the second and fourth input terminals 31b, 31d. Then, output signals are taken out of the first to eighth output terminals. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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