When mixing a 200 MHz RF signal with a 150 MHz LO, which frequency would appear at the mixer output before filtering?

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Multiple Choice

When mixing a 200 MHz RF signal with a 150 MHz LO, which frequency would appear at the mixer output before filtering?

Mixers generate both sum and difference frequencies of the two input signals due to their nonlinear mixing action. So the output contains |f_RF + f_LO| and |f_RF − f_LO|. With a 200 MHz RF signal and a 150 MHz LO, the mixer produces 350 MHz (sum) and 50 MHz (difference). Therefore a 350 MHz component would appear at the mixer output before any filtering (the 50 MHz component would also be present, but 350 MHz is the valid sum-product frequency listed among the options).

Mixers generate both sum and difference frequencies of the two input signals due to their nonlinear mixing action. So the output contains |f_RF + f_LO| and |f_RF − f_LO|. With a 200 MHz RF signal and a 150 MHz LO, the mixer produces 350 MHz (sum) and 50 MHz (difference). Therefore a 350 MHz component would appear at the mixer output before any filtering (the 50 MHz component would also be present, but 350 MHz is the valid sum-product frequency listed among the options).

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