초록 ▼

A range dispersion sensor operative to detect objects of a preselected height “h”operates on quarterwave interference principles. Electromagnetic energy is modulated at a first frequency f1 such that objects of the preselected height h disposed upon a background create a quarter-wave length reflecto

A range dispersion sensor operative to detect objects of a preselected height “h”operates on quarterwave interference principles. Electromagnetic energy is modulated at a first frequency f1 such that objects of the preselected height h disposed upon a background create a quarter-wave length reflector. A beam of electromagnetic energy reflected from an object of height h and its proximate background interferes destructively to create a null signal. Effects of non-uniform reflectivity are normalized by modulating the beam at a second frequency f2 selected to not create constructive or destructive interference effects with objects of the preselected height. The ratio of the two signals is taken thereby normalizing the effects of non-uniform reflectivity, and the resultant ratio is indicative of the height of the objects.

대표청구항 ▼

A range dispersion sensor comprising: a source operative to provide an output beam of electromagnetic energy; a modulator associated with the source and operative in conjunction therewith to modulate the output beam at a first frequency “f1”with a second frequency “f2”; means for directing said beam

A range dispersion sensor comprising: a source operative to provide an output beam of electromagnetic energy; a modulator associated with the source and operative in conjunction therewith to modulate the output beam at a first frequency “f1”with a second frequency “f2”; means for directing said beam of electromagnetic energy onto a target zone for reflection therefrom; means for detecting the reflected energy and providing a first detector signal corresponding to detected energy modulated at f1 and a second detector signal corresponding to detected energy modulated at f2; and processing means for receiving and comparing said first and second detector signals and providing an output signal corresponding to the ratio thereof said output signal indicative of the range dispersion of said target zone.