87results about "Transmission shutdown/eye-safety" patented technology

Circuitry for monitoring the operation of an optoelectronic transceiver includes a sequence of interconnected signal processing circuits for processing an analog input signal and producing a digital result signal, where the analog signal represents one or more operating conditions of the optoelectronic transceiver. The sequence of signal processing circuits include gain circuitry for amplifying or attenuating the analog input signal by a gain value to produce a scaled analog signal, an analog to digital converter for converting the scaled analog signal into a first digital signal, and digital adjustment circuitry for digitally adjusting the first digital signal to produce the digital result signal. The digital adjustment circuitry includes shifting circuitry configured to shift an input digital signal in accordance with a shift value so as to produce a digital shifted signal. The digital result signal is stored in memory in predefined locations accessible by a host.

A system and method for providing eye-safety protection during operation of distributed Raman amplifiers based on the application of continuous out-of-band amplified spontaneous scattering (ASS) monitoring in an optical communication network span coupled to the Raman amplifier, and real-time detection and analysis of changes in the monitored ASS power level, The system includes at least one Raman pump for introducing Raman energy into the span, a monitoring unit for performing the continuous ASS monitoring, and a control unit operative to detect and analyze in real-time changes in the ASS power, and upon determination that such changes indicate an open span, to reduce the level of the Raman pump energy entering the span to a safe level.

An optical amplifier comprises an active fiber (1) a pump unit (2) spaced from the active fiber and adapted to give a nominal, continuous pump power in an operational state, and a pump fiber (3) adapted to transfer optical pump power from the pump unit (2) to the active fiber (1). Moreover, in a safety state, the pump unit (2) is adapted to give a pulsed pump power whose mean power is lower than a prescribed safety limit. A method of preventing emission of optical power exceeding a prescribed safety limit on interruption of an optical fiber (3) which transfers pump power from a pump unit (2) to an active fiber (1), comprises changing the mean power of the pump power in response to a signal received from the active fiber (1) so that the mean power assumes a value below said safety limit if said signal is not received, and assumes a nominal value if said signal is received.