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:
Jun. 17, 2025
Filed:
May. 31, 2022
Nec Laboratories America, Inc., Princeton, NJ (US);
Fatih Yaman, Princeton, NJ (US);
Yue-Kai Huang, Princeton, NJ (US);
Ezra Ip, West Windsor, NJ (US);
Hussam Batshon, Monroe, NJ (US);
Eduardo Mateo Rodriguez, Tokyo, JP;
Kohei Nakamura, Tokyo, JP;
Takanori Inoue, Tokyo, JP;
Yoshihisa Inada, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
Earthquake detection via fiber sensing is provided using using a supervisory path of submarine cables wherein the supervisory system/path of a submarine optical cable conveys portion(s) of an optical signal back to an origin location periodically—i.e., at every repeater location. Advantageously, since it is known where a returning signal is coming from, a resolution equivalent to an undersea span length may be determined—which is sufficient for wide area disturbances such as earthquakes. The returned signal is sufficiently strong such that the signal-to-noise ratio of a returned/received signal is not limited by the ASE noise of the amplifiers. The returned signal is much larger as compared to a normal distributed acoustic sensing (DAS) return signal since the return signal according to aspects of the present disclosure is directed backward via an optical coupler/reflector/circulator having a much larger coupling ratio as compared to normal Rayleigh back scattering utilized in DAS.