ACOUSTIC LOG Russian patent published in 2009 - IPC G01P3/42 

FIELD: physics; measurement.

SUBSTANCE: acoustic log incorporates a transmission path with variable-duration pulse shaper, outputs of which are connected to control inputs of phase discriminator. To the latter the receiving path output is also connected. Phase discriminator output is connected to variable-frequency generator, an output of the latter is connected to pulse shaper input via frequency divider, adder unit, connected between the receiving path output and the log measuring system. The log circuit incorporates a correction generating unit provided with a multiplier and a memory element. Multiplier control inputs are connected to outputs of pulse shaper, receiving path and memory element. Multiplier output is connected to one of the adder inputs.

EFFECT: improved accuracy of speed measuring due to compensation of bias caused by echo-signal Doppler spectrum shift.

2 dwg