METHOD FOR MEASURING SIGNALS OF ELECTRIC PROBING Russian patent published in 1996 - IPC

FIELD: geophysics. SUBSTANCE: invention refers specifically to geoelectroprospecting and is meant for usage with investigating geoelectric structure of lithosphere and monitoring its changes. Electric probing with direct current is carried out with the help of probing signal in the form of sequence of rectangular bipolar pulses with preset period. Key reference signal is formed. Signal of electric probing is received and its synchronizing detection is accomplished with usage of key reference signal as well as integration. Key detected signal is obtained. Then additional reference signal phase-shifted through quarter of period of probing signal is formed, synchronizing detection of signal of electric probing is carried out with the use of additional reference signal and integration and additional detected signal is generated. After this difference of key and additional detected signals is found. Subtraction of signals detected in synchronism with phase shift of reference signals through quarter of period of probing signal makes it possible to suppress noise with strong correlation couplings on which mentioned phase shift has no influence. EFFECT: increased noise immunity. 1 dwg