DEVICE FOR QUADRATURE RECEPTION OF FREQUENCY-KEYED SIGNALS Russian patent published in 2005 - IPC

FIELD: radio engineering; digital data transmission and reception systems.

SUBSTANCE: proposed device that can be used for receiving continuous-phase frequency-keyed signals with frequency keying index β = 0.5 functions as follows. Signal is divided into cophasal and quadrature components by mixing it with reference signals spaced π/2 apart and low-frequency quadrature components are separated; low-voltage quadrature components are multiplied; results of multiplication of half-clock frequency voltage by phase locked loop signal are used for generating reference signals; cophasal and quadrature components are differentiated; cophasal component is multiplied by differentiated quadrature components and the latter, by differentiated cophasal component; differences between output voltages of first and second multipliers are calculated, whereupon differential voltage is filtered off; signal obtained is supplied to output of frequency-keyed signal quadrature reception device.

EFFECT: enhanced noise immunity in reception of minimal frequency shift phase-keyed signals.

1 cl, 6 dwg