| 摘要 |
PROBLEM TO BE SOLVED: To attain improvement in reception sensitivity by suppressing beats caused by a higher harmonic wave component that may occur in generation of two local oscillation signals, in a reception circuit of a double conversion system. SOLUTION: An LPF 78 is provided between a 2-frequency divider circuit 76 which supplies S<SB>LO2</SB>to a second mixer circuit 60 and the second mixer circuit 60. The LPF 78 removes the higher harmonic wave component of S<SB>LO2</SB>that may occur in the 2-frequency divider circuit 76. Thus, even if the higher harmonic wave component of S<SB>LO1</SB>that may occur in an n-frequency divider circuit 72 is turned through a semiconductor substrate or the like into the second mixer circuit 60, mixing with the higher harmonic wave component of S<SB>LO2</SB>does not occur and generation of a signal component at a frequency IF2 caused by mixing of higher harmonic waves is prevented. COPYRIGHT: (C)2007,JPO&INPIT
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