Radio signals reception by frequency changing method - involves input signal division between two signal paths, and mixing with oscillator signals whose phases differ by 180 degrees

摘要

The mirror signal is suppressed. The possibly preamplified or attenuated input signal (U2, U'2) is divided between two paths. Each signal (U2, U'2) is mixed with oscillator signals of the same frequency but shifted in phase by 180 deg. w.r.t. each other. The mixed signal (U'3) of one signal path is shifted in phase by 180 deg. w.r.t. the mixed signal in the other signal path. These two signals (U4, U'4) are combined into the final i.f. signal &U5).