Optical mandrel, optical-fiber assembly including an optical mandrel, and system for detecting an acoustic signal incident on an optical-fiber assembly

A method, comprising:

• directing a source optical signal into an end of an optical-fiber assembly that includes an optical fiber having at least one section each wrapped multiple turns around a respective one of at least one mandrel and each including respective mandrel zones;
• receiving, from the end of the optical-fiber assembly, a return optical signal;
• selecting a first mandrel zone of one of the at least one section of the optical fiber in response to a first component of the return optical signal redirected by the first mandrel zone;
• and
• determining that an acoustic signal is incident on the one of the at least one mandrel around which the one of the at least one section of the optical fiber is wrapped in response to the first component of the return optical signal.

A non-transitory computer-readable medium storing data that when executed by, or used to configure, an electronic circuit causes the electronic circuit, or one or more other electronic circuits under the control of the electronic circuit:

• to direct a source optical signal into an end of an optical-fiber assembly that includes an optical fiber having at least one section each wrapped multiple turns around a respective one of at least one mandrel and each including respective mandrel zones;
• to receive, from the end of the optical-fiber assembly, a return optical signal;
• to select a first mandrel zone of one of the at least one section of the optical fiber in response to a first component of the return optical signal redirected by the first mandrel zone;
• and
• to determine that an acoustic signal is incident on the one of the at least one mandrel around which the one of the at least one section of the optical fiber is wrapped in response to the first component of the return optical signal.