Laser System for Precise, Unambiguous Range Measurements
TBMG-220
11/01/2005
- Content
The Modulation Sideband Technology for Absolute Range (MSTAR) architecture is the basis of design of a proposed laser-based heterodyne interferometer that could measure a range (distance) as great as 100 km with a precision and resolution of the order of 1 nm. Simple optical interferometers can measure changes in range with nanometer resolution, but cannot measure range itself because interference is subject to the well-known integer-multiple-of-2p- radians phase ambiguity, which amounts to a range ambiguity of the order of 1 µm at typical laser wavelengths. Existing rangefinders have a resolution of the order of 10 µm and are therefore unable to resolve the ambiguity. The proposed MSTAR architecture bridges the gap, enabling nanometer resolution with an ambiguity range that can be extended to arbitrarily large distances.
- Citation
- "Laser System for Precise, Unambiguous Range Measurements," Mobility Engineering, November 1, 2005.