A long-distance high-precision optical fiber interference sensing and positioning system includes a sensing light path, a control terminal, a light source module, a front-end optical processing module, a back-end optical processing module, a photoelectric conversion module, a digital signal collection module and a MCU central processing module. The control terminal is provided with a signal processing and positioning device for calculating and positioning sensing signal positioning information. The present system can solve the security problem of an ultra-long-distance optical cable, can send alarm information in a timely manner with regard to an intrusion event by means of vibration positioning, and can also solve the problem of occupation of an optical cable channel, and improves the utilization efficiency of the optical cable by means of wavelength division multiplexing technology.

An operation method of a network device and a control chip of the network device are provided. The network device receives an input signal through a fiber medium. The operation method includes the following steps: setting a target speed of the network device to a first speed; transmitting and/or receiving a data at the first speed; and setting the target speed of the network device to a second speed which is different from the first speed when the amplitude or energy of the input signal is not greater than a threshold.

An operation method of a network device and a control chip of the network device are provided. The network device receives an input signal through a fiber medium. The operation method includes the following steps: setting a target speed of the network device to a first speed; transmitting and/or receiving a data at the first speed; and setting the target speed of the network device to a second speed which is different from the first speed when the amplitude or energy of the input signal is not greater than a threshold.

A fiber optic distribution terminal includes a cable spool rotatably disposed within an enclosure; an optical power splitter and a termination region carried by the cable spool; an optical cable deployable from the enclosure by rotating the cable spool by pulling on a connectorized end of the optical cable; and splitter pigtails extending between the optical power splitter and the termination region. One fiber of the optical cable extending between the connectorized end and the splitter input. The other fibers of the optical cable extend to a multi-fiber adapter.

A fiber optic distribution terminal includes a cable spool rotatably disposed within an enclosure; an optical power splitter and a termination region carried by the cable spool; an optical cable deployable from the enclosure by rotating the cable spool by pulling on a connectorized end of the optical cable; and splitter pigtails extending between the optical power splitter and the termination region. One fiber of the optical cable extending between the connectorized end and the splitter input. The other fibers of the optical cable extend to a multi-fiber adapter.

A laser device for optical communication comprises a first laser unit connected to a first optical fiber for supplying a transmission laser beam thereto. wherein the laser device is configured for providing a reference laser beam in addition to the transmission laser beam. For providing the reference laser beam the laser device further includes a second laser unit connected to a second optical fiber for supplying the reference laser beam to the second optical fiber. The first laser unit is configured for providing the transmission laser beam as a linear polarized beam that is polarized in a first polarization direction, and the second laser unit is configured for providing the reference laser beam as a linear polarized beam that is polarized in a second polarization direction. The first optical fiber and the second optical fiber are formed of polarization maintaining optical fibers, and the laser device further includes a polarization combiner connected to a third polarization maintaining optical fiber for conveying the transmission laser beam and the reference laser beam to an optical output of the laser device.

A laser device for optical communication comprises a first laser unit connected to a first optical fiber for supplying a transmission laser beam thereto. wherein the laser device is configured for providing a reference laser beam in addition to the transmission laser beam. For providing the reference laser beam the laser device further includes a second laser unit connected to a second optical fiber for supplying the reference laser beam to the second optical fiber. The first laser unit is configured for providing the transmission laser beam as a linear polarized beam that is polarized in a first polarization direction, and the second laser unit is configured for providing the reference laser beam as a linear polarized beam that is polarized in a second polarization direction. The first optical fiber and the second optical fiber are formed of polarization maintaining optical fibers, and the laser device further includes a polarization combiner connected to a third polarization maintaining optical fiber for conveying the transmission laser beam and the reference laser beam to an optical output of the laser device.

A communication system transmits a data signal between a transmitter and a receiver. A service provider operates the communication system for a client. When the data signal is received at the receiver, the data signal is decoded and the service provider decides whether the decoded data signal is accurate or whether the decoded data signal should be rejected. The service provider transmits the decoded data signal and its determination as to its accuracy to the client. Metadata including information about the transmission of the data signal is also provided to the client so that the client can make its own determination regarding whether to accept or reject the decoded data signal.

An optical module includes an interface electrically connected to an external device to receive a data signal to be transmitted, a signal processor configured to perform serialization and signal modulation on the received data signal, an optical transceiver configured to generate an optical transmission signal by receiving a direct current (DC) light source, in which a plurality of light sources having different wavelengths are multiplexed, from an optical power supply and performing optical modulation thereon through the serialized and modulated data signal, and an optical fiber connector configured to output the generated optical transmission signal to the external device and receive an optical reception signal from the external device.

An optical module includes an interface electrically connected to an external device to receive a data signal to be transmitted, a signal processor configured to perform serialization and signal modulation on the received data signal, an optical transceiver configured to generate an optical transmission signal by receiving a direct current (DC) light source, in which a plurality of light sources having different wavelengths are multiplexed, from an optical power supply and performing optical modulation thereon through the serialized and modulated data signal, and an optical fiber connector configured to output the generated optical transmission signal to the external device and receive an optical reception signal from the external device.