The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 05, 2009
Filed:
Mar. 03, 2005
Jonathan Young, Newburyport, MA (US);
Harry Vig, N. Billerica, MA (US);
Michael J. Lagasse, Nahant, MA (US);
Jonathan Young, Newburyport, MA (US);
Harry Vig, N. Billerica, MA (US);
Michael J. Lagasse, Nahant, MA (US);
MagiQ Technologies, Inc., New York, NY (US);
Abstract
A method of autocalibrating a quantum key distribution (QKD) system () is disclosed. The QKD system includes a laser (() that generates photon signals in response to a laser gating signal (S) from a controller (). The method includes first performing a laser gate scan () to establish the optimum arrival time (T) of the laser gating signal corresponding to an optimum—e.g., a maximum number of photon counts (N)—from a single-photon detector (SPD) unit () in the QKD system when exchanging photon signals between encoding stations (Alice and Bob) of the QKD system. Once the optimal laser gating signal arrival time (T) is determined, the laser gate scan is terminated and a laser gate dither process () is initiated. The laser dither involves varying the arrival time (T) of the laser gating signal around the optimum value of the arrival time T. The laser gate dither provides minor adjustments to the laser gating signal arrival time to ensure that the SPD unit produces an optimum (e.g., maximum) number of photon counts.