| 摘要 |
PURPOSE:To obtain a sufficient gain and to prevent the occurrence of unnecessary radiated waves by forming local oscillating circuits of repeaters so that local oscillation frequencies generated for each frequency conversion do not coincide with each other. CONSTITUTION:In a repeating circuit 4a, the high frequency signal having a frequency f1 received from an antenna is inputted to a mixer circuit MX1 and is mixed with the frequency from a local oscillating circuit 6a there and is mixed with the frequency from a local oscillating circuit 6b by a mixer circuit MX2 and is outputted from the antenna as a high frequency transmission signal. In a repeating circuit 4b, a received signal having a frequency f4 passes mixers MX1 and MX2 and is outputted from an antenna similarly. In such a case, oscillation frequencies of local oscillating circuits 6a-6d are made different from one another to reduce the occurrence of unnecessary radiated waves due to interference among local oscillation signals.
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