METHOD AND CONVERTER FOR FREQUENCY CONVERSION INCLUDING IMAGE INTERFERENCE SUPPRESSION Russian patent published in 2006 - IPC H03D7/18 

FIELD: radio engineering; superheterodyne reception of radio signals to suppress image interference.

SUBSTANCE: proposed method involves mixing of input signal with signal of built-in heterodyne followed by its passage through intermediate-frequency filter. Input signal is branched off prior to mixing to two channels wherein signals are phased out so as to produce cophasal useful signal and antiphase image interference signal. Phased-out signals are summed up. This method is implemented by converter that has mixer 3, intermediate-frequency filter 4, heterodyne 5, adder 2, and image-interference carrier wave half-cycle delay line 1. Heterodyne frequency is chosen considering that carrier frequency of useful signal should be higher than that of image interference by even number of times.

EFFECT: enlarged functional and image interference suppression capabilities.

2 cl, 3 dwg