Patent application number | Description | Published |
20110033184 | Side Band Pilot Tone for Digital Signal Processing in Polarization Multiplexed Coherent Optical Communication System - A method comprising generating a plurality of first symbols that correspond to a side band pilot tone (SBPT) signal for a plurality of data streams, mapping the first symbols into a plurality of second symbols that correspond to a plurality of signal components of the polarization multiplexed (PM) optical signal, and transmitting the second symbols in a plurality of data blocks of a PM optical signal. An apparatus comprising at least one processor coupled to a memory and configured to obtain a data block that comprises a plurality of SBPTs in a received PM optical signal, estimate a set of values for a carrier frequency and a polarization state, update a tap weight of a master equalizer based on the estimated set of values, and update a plurality of slave equalizers based on the updated tap weight of the master equalizer. | 02-10-2011 |
20120033965 | Method and Apparatus for Broadband Carrier Frequency and Phase Recovery in Coherent Optical System - A digital apparatus comprising a fast Fourier transform (FFT) module configured to transform a time domain optical signal into a frequency domain optical signal, a circular shifter coupled to the FFT module and configured to provide coarse frequency offset compensation to the frequency domain optical signal based on an estimated frequency offset; and a frequency offset estimation module coupled to the circular shifter and configured to provide the estimated frequency offset based on a power spectrum of the frequency domain optical signal or a data block header autocorrelation of the time domain optical signal. | 02-09-2012 |
20140185978 | HYBRID INTEGRATION USING FOLDED MACH-ZEHNDER MODULATOR ARRAY BLOCK - An apparatus comprising a modulation block comprising a plurality of modulators, wherein each of the plurality of modulators comprises an optical input port and an optical output port, and wherein all of the optical input ports and all of the optical output ports are positioned on one face of the modulation block. Another apparatus comprising a modulation block comprising one or more Mach-Zehnder modulators (MZMs), wherein each MZM is coupled to an optical input port, an optical output port, and at least one electrical trace, wherein all of the optical input ports and all of the optical output ports are positioned on a first side of the modulation block, and wherein all of the electrical traces are positioned on a second side of the modulation block, and a planar lightwave circuit (PLC) coupled to the modulation block via an optical interface. | 07-03-2014 |
20140185980 | Silicon-On-Insulator Platform for Integration of Tunable Laser Arrays - An apparatus comprising a silicon-on-insulator (SOI) platform comprising an optical component network. An apparatus comprising an optical component network monolithically grown on a SOI platform, and an optical device coupled to the optical component network. A method comprising generating an optical signal using a silicon-based optical component, applying an electrical signal to the optical component, and tuning a wavelength of the optical signal based on the electrical signal. | 07-03-2014 |
20150071641 | Optical Transmitters With Unbalanced Optical Sidebands Separated By Gaps - An apparatus comprising a transmitter configured to generate an optical signal comprising a carrier modulated with at least two sidebands modulated with information, wherein the information introduces a separation gap in a frequency domain between the sidebands and the carrier, wherein one of the sidebands is an undesired sideband and another one of the sidebands is a desired sideband with a higher power intensity than the undesired sideband. A method comprising receiving an optical carrier from a light source and modulating the optical carrier with at least two sidebands modulated with information, wherein the information introduces a separation gap in a frequency domain between the sidebands and the optical carrier, wherein one of the sidebands is an undesired sideband and another one of the sidebands is a desired sideband having a higher power intensity than the undesired sideband. | 03-12-2015 |
20150125160 | METHOD AND APPARATUS FOR DIRECTLY DETECTED OPTICAL TRANSMISSION SYSTEMS BASED ON CARRIERLESS AMPLITUDE-PHASE MODILATION - Methods and apparatus for directly detected optical system based on gapped CAP modulation and DSP Methods for generation and reconstruction of gapped CAP signal are disclosed. An apparatus for direct detection transmission for CAP modulated signal with two unbalanced optical sidebands separated by gaps is disclosed, in which a gapped CAP signal is generated, converted, and passed to an optical filter for unbalanced sidebands generation and wavelength locking before being transmitted over an optical link. Direct detection is performed on the optical signal and passed to gapped matching filters. Channel equalization is performed and the signal information is decoded to binary data. | 05-07-2015 |
20150212346 | Interdigitated Optical Modulator - An optical modulator comprises a silicon substrate, a buried oxide (BOX) layer disposed on top of the silicon substrate, and a ridge waveguide disposed on top of the BOX layer and comprising a first n-type silicon (n-Si) slab, a first gate oxide layer coupled to the first n-Si slab, a first p-type silicon (p-Si) slab coupled to the first gate oxide layer, and a light propagation path that travels sequentially through the first n-Si slab, the first gate oxide layer, and the first p-Si slab. | 07-30-2015 |
20150295649 | METHOD AND SYSTEM FOR PERFORMING FIBER NONLINEARITY COMPENSATION FOR OPTICAL 16QAM - A method for reducing link fiber nonlinearities executed by a processor. The method includes decomposing a high order quadrature amplitude modulation (QAM) input into a plurality of sub-components. The method includes applying a plurality of logical operations to the plurality of sub-components. The method includes determining a non-linear compensation term based on the applying the plurality of logical operations to the plurality of sub-components. | 10-15-2015 |