Integrated polarimeter in an optical line system

Transmission device, transmission system, and transmission method

Integrated polarimeter in an optical line system

Optical transmission device and optical transmission method

OPTICAL TRANSMISSION SYSTEM, OPTICAL TRANSMISSION DEVICE AND NETWORK CONTROL DEVICE

Proactive channel probing for wavelength switching in optical transmission systems

Integrated polarimeter in an optical line system

Signal loopback circuit and signal loopback method

SYSTEM AND METHOD FOR OPTICAL SIGNAL TRANSMISSION

Wavelength control method and apparatus

Optical fiber polarization multiplexing

Out-of band management of fiber optics systems and devices

Optical add/drop multiplexer and method for adding/dropping optical signal

Method and apparatus for providing a differential latency

Determining asymmetries in a communication network

Communications device and method

Determining asymmetries in a communication network

Method and arrangement for in service Raman gain measurement and monitoring

Method for monitoring wavelength-division multiplexed signal

METHOD OF ASSESSING FAILURE IN TRANSMISSION PATH OPTICAL FIBER, AND APPARATUS OF SAME

Bit error generation system for optical networks

Optical node, optical network system, and method for measuring polarization mode dispersion

Measurement of polarization mode dispersion or differential group delay of an optical path

High speed in-service optical network testing

Optical communication apparatus and optical wavelength multiplexing transmission system

Method and system for distributed measurement and compensation of chromatic dispersion in an optical network

Optical signal transmission apparatus

Automatic power restoring method and optical communication system

Optical transmission apparatus and optical communication system

Pulsed high loss loop back signalling scheme

Automatic power restoring method and optical communication system

Optical transmission apparatus

Optical transmission system with automatic signal level adjustment and startup functions

Method and apparatus for monitoring an optical network signal

Optical telecommunications network terminal, an installation including the terminal, and a method of detecting a break in optical transmission means

Optical network and amplifier node therefore

System and method for subcarrier modulation as supervisory channel

Optical transmission system

Optical transmission systems and amplifier control apparatuses and methods

Methods and apparatus for sensing multiple wavelengths simultaneously in a single wavelength sensing device

Wavelength-selective optical signal processing device

Supervising system, supervising apparatus and supervising method of supervising optical transmission line

Optical Supervisory Channel for High Span Loss Optical Communication Systems

Submarine observation apparatus and submarine observation system

Observation apparatus and observation system

Optical transmission system

System and method for subcarrier modulation in ISM band as supervisory channel

System and method for subcarrier modulation as supervisory channel

Optical transmission system with automatic signal level adjustment and startup functions

Transmission of supervisory data in an optical communication system

Method for per-channnel power control in a DWDM network by means of an algorithm for adjusting the power of a dummy signal and the input power of an optical amplifier via channel-average Q-factor measurement

Laser transmitter capable of transmitting line data and supervisory information at a plurality of data rates

Method and device of analyzing a signal transmitted via a communication link

Dynamic control of power loss in an optical fiber by contrapropagation of a supervisory channel

Optical transmission system

Optical transmission system and amplifier control apparatuses and methods