Summator of radio pulse signals

A high-quality summator of radio-frequency pulse signals was built for intermediate-frequency stages in radar receivers, particularly in channels where phase-keyed quasi-noise signals appearing with noise interference are processed. The summing circuit is connected on the input side to a commutator and is followed by a band-pass output amplifier. The commutator, containing 8 pairs of independently driven transistor switches, receives signals from a band-pass input amplifier through an 8-tap delay line and from a code generator through a control circuit. The prototype of this summator was tested and found to produce output signals with sufficiently small deviations of phase shifts upon cophasal cummation of antiphasal summation as well as sufficiently small amplitude nonuniformity of the order of a few percent only, the latter being achieved by inclusion of trimmers in the commutator or in the summing circuit. The summator is suitable for a 50 MHz tuning range, its delay line being designed for radio signals of 8 tau (tau = 1.6 microns) duration.