Ciena

About: Ciena is a company organization based out in Hanover, Maryland, United States. It is known for research contribution in the topics: Signal & Node (networking). The organization has 1259 authors who have published 1557 publications receiving 25989 citations.

Systems and methods for adaptive gain control to compensate OSNR penalty caused by side-lobe of MEMS-based reconfigurable optical add-drop multiplexers

Abstract: The present invention provides systems and methods to adaptively control amplifier target power to maintain signal launching power as per design in networks with wavelength selective switch (WSS)-based reconfigurable optical add-drop multiplexers (ROADMs) using micro-electromechanical system (MEMS). Accordingly, signal OSNR does not collapse faster for WSS-based ROADMs than other similar configured system without WSS-based ROADM. In order to correct amplifier target power, the present invention utilizes system information about side-lobe size and OSNR at each amplifier. Related information, such as ASE level and size of side-lobes at each channel from upstream amplifiers, is passed to the network controller at each amplifier. Meanwhile, with target signal level and local WSS attenuation setting (given side-lobe size vs. WSS attenuation known) of each channel, the amplifier calculates what is total output power should be and adaptively maintains that power.

Sample timing control in an optical receiver

Abstract: A method of compensating phase error between parallel digital signals of a received optical signal, in a coherent optical receiver. A phase differential between the digital signals is determined. A digital skew is imposed between the digital signals, an amount of skew imposed being an integer number of sample periods calculated to most nearly compensate the phase differential. The skewed digital signals are then digitally processed, in the frequency domain, to compensate a residual portion of the phase differential.

Data connectivity systems and methods through packet-optical switches

Abstract: Systems and methods for providing a data service through a packet-optical switch in a network include, subsequent to defining a loop-free forwarding topology for the data service in the network, if the packet-optical switch is a degree 2 site for the data service, providing the data service through the packet-optical switch at a Layer 1 protocol bypassing a partitioned packet fabric of the packet-optical switch; and if the packet-optical switch is a degree 3 or more site for the data service with multi-point connectivity, providing the data service through the packet-optical switch at the Layer 1 protocol and at a packet level using the partitioned packet fabric to provide the data service between the multi-point connectivity and to associated OTN connections for each degree of the degree 3 or more site.

Nonlinear Compensation in Optical Communications Systems With Normal Dispersion Fibers Using the Nonlinear Fourier Transform

Abstract: We investigate the computational cost of the nonlinear Fourier transform (NFT) based on the Zakharov–Shabat scattering problem as a nonlinear compensation technique for quadrature-phase-shift keyed (QPSK) signals with raised cosine frequency characteristic in optical fiber transmission systems with normal dispersion fibers. We show that the primary sources of computational errors that arise from the use of the NFT is the finite eigenvalue resolution of the left and the right reflection spectra. We show that this effect and, consequently, the computational cost of the NFT as a nonlinear mitigation technique in the normal dispersion regime increases exponentially or faster with both the channel power and the number of symbols per data frame even using the most efficient NFT algorithms that are currently known. We find that the computational cost of this approach becomes unacceptably large at data frame lengths and powers that are too small for this approach to be competitive with standard transmission methods. We explain the physical reasons for these limits.

System and methods for connections using automatically switched optical network control planes

Abstract: Systems and methods for connections on an Automatically Switched Optical Network (ASON) network including an ASON database and path computation algorithm, mechanisms for Ethernet connections over ASON, and mechanisms for label negotiation for SNCs are provided. Advantageously, the present invention provides mechanisms for ASON path computation and virtual topology management, Ethernet connection establishment, modification, and deletion in ASON networks, and label negotiation without requiring binding and releasing of connections before label negotiation.