| 摘要 |
PURPOSE:To prevent an input signal from being leaked to an output terminal by performing mixing in two transistors TRs and operating their input phases and output phases to synthesize them. CONSTITUTION:A local oscillation frequency f1 inputted from an input terminal 1 is supplied to FETs 13 and 14 with 90 deg. phase difference by a 90 deg. hybrid 10. Outputs of FETs 13 and 14 are synthesized with phases opposite to each other by a 90 deg. hybrid 11. Consequently, the local oscillation frequency f1 does not appear in an output terminal 3. Meanwhile, an intermediate frequency f2 is inputted to FETs 13 and 14 with phases opposite to each other by a 180 deg. hybrid 12. Consequently, a sum frequency f1+f2 of the local oscillation frequency and the intermediate frequency is obtained in the output terminal 3 through the 90 deg. hybrid 11. Even if local oscillation signals which have 90 deg. phase difference by the 90 deg. hybrid 10 are reflected in FETs 13 and 14, they pass the 90 deg. hybrid again to be synthesized with phases opposite to each other, and therefore, they do not appear in the input terminal 1. |
