Abstract: The invention relates to a system for measuring velocity. In one aspect of the invention, the system comprises a laser emitting device, an optics assembly, a combiner and a signal processor. The laser emitting device generates a frequency-modulated laser signal. The optics assembly splits the frequency modulated signal into a plurality of laser signals, and directs the split signals to a target and receives at least one signal reflected from the target. The combiner receives one of the split signals transmitted via one signal path and the at least one reflected signal transmitted via another signal path, and multiplies the received signals. The signal processor extracts velocity information from the multiplied signal.
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.