Multiple simultaneous optical frequency measurement
US6509729B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 9, 2001 |
| Grant date | Jan 21, 2003 |
| Priority date | — |
| Expiry date | Feb 2, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R23/175
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A signal processing apparatus for providing concurrent electrical frequency measurements of multiple, time-coincident signal inputs. In one embodiment of the present invention, an input signal is received that contains a plurality of individual signals independent of each other in frequency, phase, and electrical amplitude. A power splitter splits the input signal into two separate input signals. A delay line introduces a time delay to one of the two separate input signals. Two Bragg cells within a channelized optical phase measurement (COPM) device modulates two optical carrier signals with the delayed and non-delayed input signals, respectively, separating the modulated delayed and non-delayed input signals into multiple time-concurrent frequency channel signals. Upon exiting the Bragg cells, the two optical beams interfere spatially to develop an interference pattern along the phase and frequency channel number axes of a photodetector array. The resulting spatial intensity pattern phase variation is decoded to provide coarse frequency, phase, and amplitude measurements. A frequency encoder receives the photodetector outputs, corrects phase and amplitude data offsets, and convert…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.