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:
Dec. 30, 2025
Filed:
Sep. 01, 2021
Ntt, Inc., Tokyo, JP;
Atsushi Taniguchi, Musashino, JP;
Hirokazu Takahashi, Musashino, JP;
Hideki Nishizawa, Musashino, JP;
NTT, Inc., Tokyo, JP;
Abstract
A transmission device () includes a modulation unit () that modulates photons with a predetermined data pattern, a synchronization signal generation unit () that generates a frame synchronization signal of a random number data pattern, an identification signal generation unit () that divides the frame into a plurality of subframes and generate a subframe identification signal indicating a subframe, and a transmission unit () that transmits the photons modulated by the modulation unit (), the frame synchronization signal, and the subframe identification signal. A reception device () includes a reception unit () that receives the photons, the frame synchronization signal, and the subframe identification signal transmitted from the transmission unit (), a decoding unit () that detects and decodes a data pattern from the photons, a time measurement unit () that measures an elapsed time from the subframe identification signal until a photon is detected in each subframe, and a detection time calculation unit () that calculates a photon detection time from the frame synchronization signal to photon detection in one frame, based on the elapsed time.