US 11,982,552 B2
Vibration detection using phase recovered from an optical transponder with coherent detection
Ezra Ip, West Windsor, NJ (US); and Yue-Kai Huang, Princeton, NJ (US)
Assigned to NEC Corporation, Tokyo (JP)
Filed by NEC Laboratories America, Inc., Princeton, NJ (US)
Filed on Dec. 7, 2021, as Appl. No. 17/544,806.
Claims priority of provisional application 63/192,188, filed on May 24, 2021.
Claims priority of provisional application 63/122,611, filed on Dec. 8, 2020.
Prior Publication US 2022/0236083 A1, Jul. 28, 2022
Int. Cl. G01D 5/353 (2006.01); G01H 9/00 (2006.01); H04B 10/61 (2013.01)
CPC G01D 5/35361 (2013.01) [G01H 9/004 (2013.01); H04B 10/6165 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A system for simultaneous coherent optical fiber transmission and vibration sensing comprising:
an optical fiber transmission medium;
a transceiver in optical communication with the optical fiber transmission medium, the transceiver including
a coherent optical receiver responsive to a received optical signal and a local oscillation signal for detecting a received optical signal carrier wave; and
a digital signal processor configured to recover digital data conveyed in the received optical signal and track optical phase of the received optical signal and determine vibration-induced strain of the optical fiber transmission medium;
wherein the digital data recovery and determination of vibration-induced strain of the fiber transmission medium are performed simultaneously; and
wherein the digital signal processor is configured to track optical phase of the received optical signal by combining phase embedded by adaptive digital signal processing elements including frequency offset compensation, adaptive time-domain equalization, and carrier phase recovery.