| Author(s): |
Ian R. Coddington; William C. Swann; Ljerka Nenadovic; Nathan R. Newbury; |
| Title: |
Rapid and precise absolute distance measurements at long range |
| Published: |
June 01, 2009 |
| Abstract: |
The ability to determine absolute distance to an object is one of the most basic measurements of remote sensing. High precision ranging has important applications in both large-scale manufacturing and in future tight formation-flying satellite missions, where rapid and precise measurements of absolute distance are critical for maintaining the relative pointing and position of the individual satellites. Using two coherent broadband fibre-laser frequency comb sources, we demonstrate a coherent laser ranging system that combines the advantages of time-of-flight and interferometric approaches to provide absolute distance measurements, simultaneously from multiple reflectors, and at low power. The pulse time-of-flight yields a precision of 3 mm with an ambiguity range of 1.5m in 200ms. Through the optical carrier phase, the precision is improved to better than 5 nm at 60 ms, and through the radio-frequency phase the ambiguity range is extended to 30 km, potentially providing 2 parts in 1013 ranging at long distances. |
| Citation: |
Nature Photonics |
| Volume: |
3 |
| Pages: |
pp. 351 - 356 |
| Keywords: |
frequency comb;formation-flying;ranging |
| Research Areas: |
Optical Metrology, Length, Remote Sensing |
| PDF version: |
 Click here to retrieve PDF version of paper (383KB) |
