Nec Corporation

Nec Laboratories America, Inc.

Eduardo Mateo Rodriquez

Fatih Yaman

Shaoliang Zhang

Yoshihisa Inada

Takanori Inoue

Ting Wang

Takaaki Ogata

Dayou Qian

An optical communication substrate includes a plurality of cores to communicate optical signals; a rectangular input delivering a pump laser, and a shaped portion to combine the optical signals and the pump laser into a ring geometry at an output.

3D waveguide for efficient coupling of multimode pump and signals to a multicore fiber amplifier

Aspects of the present disclosure describe systems, methods, and structures for providing C-band and L-band transmission exhibiting increased power efficiency by diverting a portion of C-band optical energy to an input of L-band optical amplifiers (C-seeding) while optionally employing circulators to eliminate the need for optical isolators.

C-band and L band amplifier design with increased power efficiency and reduced complexity

Methods and systems for communication with an optimized constellation include coding an input data stream to a symbol stream according to an optimized constellation that has a non-Gray bit mapping and that has neighboring points having more than one bit difference farther apart than neighboring points having one bit difference. The symbol stream is modulated onto a transmission signal and subsequently demodulated at a receiver to produce a received symbol stream. The received symbol stream is decoded to a bitstream according to an optimized constellation that has a non-Gray bit mapping and that has neighboring points having more than one bit difference farther apart than neighboring points having one bit difference.

Constellation designs with non-gray bit mapping

This invention proposes an alternative modulation format for channels that present improved performance when such channels co-propagate with existing intensity modulated channels. This modulation format is named Rhombic-QPSK (R-QPSK) and it is designed in such a way that it presents more tolerance to phase noise created by the nonlinear interaction with the legacy channels.

Rhombic-QPSK modulation for improved tolerance to nonlinearity in fiber communication systems

Disclosed are structures and methods for slicing a broadband signal into multiple, narrower bandwidth sub-bands through the use of a look-up table (LUT). An input broadband signal is first loaded by a pre-defined LUT. The LUT is designed with multiple parallel outputs, wherein each output is one individual sub-band.

Growing community of inventors

Tokyo, Japan

Eduardo Mateo Rodriquez