METHOD OF AND DEVICE FOR PHASING-OUT DESIRED-FREQUENCY SIGNALS IN SPATIALLY SEPARATED CENTRAL AND TERMINAL STATIONS Russian patent published in 1996 - IPC

FIELD: radio engineering. SUBSTANCE: device for implementing method of phasing-out desired-frequency electric signals in spatially separated central and terminal stations has in terminal station detector 1 formed by input transformer 2, nonlinear element 3, and low-frequency filter 4, amplifier 5, matching element 6, transformer-type coupling element 7, master oscillator 8 for frequency signal ω_o, and communication line 9. Device has in central station controllable delay element 10, transformer-type coupling element 11, matching element 12, phase detector 13 formed by input transformer 14, nonlinear element 15, and low-frequency filter 16, controllable phase meter 17, low-frequency filter 18, capacitor 19, first and second storage units 20 and 25, respectively, inverter 21, first and second adders 22 and 24, respectively, controllable multiplier 23, control unit 26, and change-over double-frequency oscillator 27. Phase shifts are measured at fixed low frequency at which much higher accuracy characteristics of phase shift measurements can be attained. For better accuracy, use is made of push-pull mode of measurement of phase shifts brought in by communication line and by delay element connected in series with the latter that provides for elimination of methodical error due to delay of fixed low-frequency signal when it is transmitted over communication line towards central station. EFFECT: high accuracy of phasing-out while using single communication line. 2 cl, 5 dwg