A Laser Doppler Velocimeter for Measuring the Initial Velocity of a Projectile.
NAVAL ACADEMY ANNAPOLIS MD
Pagination or Media Count:
The experiment attempted to study the feasibility of measuring the initial velocity of naval gun projectiles by the application of the optical Doppler shift - measured in a laser beam. A helium-neon was used to produce the beam of light that was split into two components. One component was reflected from the moving object causing a shift in the frequency of the beam and then recombined with the second, unshifted component to form a beat frequency. This modulated beam was heterodyned in a photomultiplier tube, producing an output voltage. The frequency of the photomultiplier signal matched the Doppler shift induced in the laser beam, and was measured by a spectrum analyzer. Author
- Test Facilities, Equipment and Methods
- Fire Control and Bombing Systems