Abstract: In various aspects, an optical connector with a built-in photodetector for detecting light in the optical connector; an adapter for detachably receiving an optical connector, comprising an electrode configured to electrically contact an electrode of the optical connector; a connection apparatus comprising an arrangement of adapters for detachably receiving a plurality of optical connectors, each adapter comprising an electrode configured to electrically contact an electrode of the respective optical connector; a system with an interface configured to make an optical connection with an optical connector and a processing unit configured to receive from the connector an indication and to generate a feedback signal indicative of said indication; and/or an optical connector responsive to light to generate an electrical signal is provided.

Abstract: In various aspects, an optical connector with a built-in photodetector for detecting light in the optical connector; an adapter for detachably receiving an optical connector, comprising an electrode configured to electrically contact an electrode of the optical connector; a connection apparatus comprising an arrangement of adapters for detachably receiving a plurality of optical connectors, each adapter comprising an electrode configured to electrically contact an electrode of the respective optical connector; a system with an interface configured to make an optical connection with an optical connector and a processing unit configured to receive from the connector an indication and to generate a feedback signal indicative of said indication; and/or an optical connector responsive to light to generate an electrical signal is provided.

Abstract: A selective WDM add-channel system and method for adding channels to a WDM (wavelength division multiplexed) signal input to produce a WDM signal output while protecting against signal collisions are provided. The method protects against signal collisions by determining channel wavelengths of add-channel signals and at least one of the WDM signal input and the WDM signal output to ensure that channels that are added to the WDM signal input have different channel wavelength than each other and the channels that are already part of the WDM signal input. The selective WDM add-channel system comprises a selective combiner and a controller and is operable to selectively combine a plurality of add-channel inputs with a WDM input signal to produce a WDM output signal based on the channel wavelengths of the add-channel input signals and at least one of the WDM input signal and the WDM output signal.

Abstract: Performance monitoring and equalization of DWDM optical links equipped with optical add/drop multiplexers (OADMs) at one or more sites is effected by selecting a direction of transmission and the end sites from the point of view of equalization. Performance monitoring and equalization of DWDM optical links equipped with optical add/drop multiplexers (OADM) is presented in this application. This approach in involves conceptually converting a multiple ends system to a “two-end” system with analogous channels (AC) to simplify the network management and equalize the DWDM channel performance. All analogous channels are treated as originating at a source analogous end and terminating at a destination analogous end for the purpose of equalization. The input power for all ACs, is adjusted at the source AE to obtain equal channel performance at the destination AE.

Abstract: A tuning system for use in a receiver of an optical transmission system. The receiver includes a data channel transporting a data signal and a monitoring channel transporting a copy of the data signal. The tuning system includes a processing module for processing the copy of the data signal to generate a control signal conveying tuning information. This tuning information is used by the receiver to alter an operating point of the receiver on the data channel. The operating point of the receiver that is susceptible to be altered by the control signal is a decision threshold applied on the data signal to discriminate one binary value from another binary value on the data channel of the receiver. This approach allows, when required or desired, tuning of the system while the system is in service. This is possible since the tuning of the system is performed using the monitoring channel, and does not disturb nor corrupt the actual data being transported on the data channel.

Abstract: Performance monitoring and equalization of DWDM optical links equipped with optical add/drop multiplexers (OADMs) at one or more sites is effected by selecting a direction of transmission and the end sites from the point of view of equalization.

Abstract: An in-line repeater implemented within a Wavelength Division Multiplexed (WDM) optical fiber communication system is shown that includes an attenuator. The communication system includes a WDM multiplexer that transmits a WDM signal including a series of WDM channels, via the in-line repeater, to a demultiplexer that separates the WDM channels into a series of output signals. Within the in-line repeater, the attenuator is coupled between two stages of a single amplifier in order to aid in the power equalization of the WDM channels at the demultiplexer. The addition of the attenuator results in the powers and OSNR of the individual WDM channels becoming closer in value, hence reducing the time and the dynamic range of transmitter power adjustments required for traditional methods to equalize the channels' powers.