FIELD: measuring technique, namely range finding.
SUBSTANCE: method comprises steps of generating periodic modulating voltage; generation and excitement of sounding waves; reception of reflected waves, propagation time interval later; Mixing received waves with part of power of sounding waves; separation of difference frequency signal; correction of periodic modulating voltage according to fluctuation of instant periods of difference frequency signal from their mean value in order to reduce difference of mean and instant values of period duration until predetermined level. It is possible to realize two variants of correction. In first variant range finding and correction are realized by the same difference frequency signal received with use of echo-waves reflected from sounded surface. In second variant correction is realized with use echo-waves received in portion of reference feeder line and range finding is realized with use of echo-waves reflected from sounded surface. Correction of modulating voltage may be performed by calculating correcting voltage summed with modulating voltage or by displacing initial readings of modulating voltage along time axis. In both variants correction is based upon mean value of difference frequency signal.
EFFECT: elimination of error at range finding.
6 cl, 2 dwg
