Abstract: A system for measuring velocity of a target is disclosed. In one embodiment, the system includes a laser device, a detector and a signal processor. The laser device produces a frequency-modulated laser beam, wherein the frequency-modulated beam is split into at least two laser beams, wherein a reflected beam comprising one split beam is directed to the target and reflected from the target. The detector detects a combination of the reflected beam and a reference beam comprising another split beam, wherein the reflected beam and the reference beam have unequal delays. The signal processor obtains velocity information from the combined beam by use of Doppler-shifted harmonies of the modulation frequency.
Abstract: A system for measuring velocity of a target is disclosed. In one embodiment, the system includes a laser device, a detector and a signal processor. The laser device produces a frequency-modulated laser beam, wherein the frequency-modulated beam is split into at least two laser beams, wherein a reflected beam comprising one split beam is directed to the target and reflected from the target. The detector detects a combination of the reflected beam and a reference beam comprising another split beam, wherein the reflected beam and the reference beam have unequal delays. The signal processor obtains velocity information from the combined beam by use of Doppler-shifted harmonics of the modulation frequency.
Abstract: The invention relates to a system for measuring velocity. In one embodiment, the system includes a laser assembly having a laser diode and a power detection diode. The laser diode emits a plurality of laser signals which are frequency-modulated, wherein a selected one of the frequency-modulated signals is directed to and reflected from a target, and wherein another selected one of the frequency-modulated laser signals transmitted via one signal path is combined with the reflected laser signal transmitted via another delayed signal path in the interior of the laser assembly. The power detection diode detects the combined signal. The system also includes a signal processor configured to obtain velocity information from the detected signal by use of the harmonic frequencies associated with the modulation frequency.