| TYCO ELECTRONICS SUBSEA COMMUNICATIONS LLC Patent applications |
| Patent application number | Title | Published |
| 20120096327 | JOINT CARRIER PHASE ESTIMATION AND FORWARD ERROR CORRECTION - Methods and systems for processing an optical signal in a communication system are disclosed. The disclosed methods yield benefits for estimation and tracking of carrier phase of received signals at a digital coherent receiver without the use of differential coding. Specifically, phase ambiguity is removed by calculating the slope of the CPE at a location where the CPE begins to lose track of the received carrier phase signal. As such, a CPE offset adjustment may be applied in accordance with the calculated slope to reduce the number of ones and zeros corrected by a FEC decoder. Thus, the FEC aided CPE scheme may be a feed forward scheme that requires no training. | 04-19-2012 |
| 20120093510 | CORRELATION -CONTROL QPSK TRANSMITTER - An optical transmitter utilizing a multi-level data modulator to produce a PDM-QPSK signal, a one-bit delay interferometer configured to correlate the multi-level data modulated signal and an optical filter configured to combine the correlated multi-level data modulated signal with one or more neighboring signals prior to transmitting over one of a plurality of optical channels. The PDM-QPSK correlated signal is configured to reduce the signal spectrum thereby increasing spectral efficiency of the transmitted signal. | 04-19-2012 |
| 20120087658 | Wavelength Selective Switch Band Aggregator and Band Deaggregator and Systems and Methods Using Same - In general, wavelength division multiplexed (WDM) communication systems may use wavelength selective switching to aggregate and/or deaggregate groups or bands of channel wavelengths. A wavelength selective switch (WSS) band aggregator may combine a plurality of channel band aggregate optical signals to produce a combined aggregate optical signal (i.e., a transmitted WDM or DWDM signal). The WSS band aggregator may also combine one or more spectral portions of broadband noise with the bands of channel wavelengths such that the spectral portion(s) of the broadband noise occupies unutilized channels in the combined aggregate optical signal. A WSS band deaggregator may separate a combined aggregate optical signal (i.e., a received WDM or DWDM signal) to produce a plurality of channel band aggregate optical signals. | 04-12-2012 |
| 20120087657 | Orthogonally-Combining Wavelength Selective Switch Multiplexer and Systems and Methods Using Same - In general, a wavelength division multiplexed (WDM) communication system may use wavelength selective switching to simultaneously pre-filter and combine groups of channel wavelengths with orthogonal polarizations to provide a pre-filtered, pair-wise orthogonal aggregate WDM optical signal. An orthogonally-combining wavelength selective switch (WSS) multiplexer may route channel wavelengths individually from different sets of channels to a common output. The orthogonally-combining WSS multiplexer may also provide substantially orthogonal polarizations for the wavelengths in the different sets of channels. The different sets of channels may include odd channels and even channels. | 04-12-2012 |
| 20120008950 | Orthogonally-Combining Interleaving Filter Multiplexer and Systems and Methods Using Same - In general, a wavelength division multiplexed (WDM) communication system simultaneously pre-filters and combines groups of wavelengths with orthogonal polarizations to provide a pre-filtered, pair-wise orthogonal aggregate WDM optical signal. In particular, an orthogonally-combining interleaving filter multiplexer provides substantially orthogonal polarizations for odd and even channel wavelengths and simultaneously pre-filters and combines the orthogonally polarized odd and even channel wavelengths using interleaver optics. The orthogonal polarizations may be provided by orientation of PM input fibers or by a polarization rotator in the orthogonally-combining interleaving filter multiplexer. | 01-12-2012 |
| 20110274442 | PILOT SYMBOL AIDED CARRIER PHASE ESTIMATION - Methods and systems for processing an optical signal in a communication system are disclosed. The disclosed methods yield benefits for estimation and tracking of carrier phase of received signals at a digital coherent receiver. Specifically, phase ambiguity is removed by the insertion of pilot symbols into a transmitted data stream. Pilot symbols are detected from a received signal, and carrier phase is estimated for the detected pilot symbols. If carrier phase track of received data symbols was lost, a correction is applied to recover the track. Coherent symbol decoding may be used which has not been possible with prior art techniques due to the possibility of phase tracking loss. | 11-10-2011 |
| 20110274119 | CONFIGURATION AND OPERATION OF INVERSE MULTIPLEXING COMMUNICATION SYSTEM - An inverse multiplexing communication path is established in at least one direction between nodes connected by a plurality of lower bandwidth bearing channels between the nodes, on which the content of a higher bandwidth signal is distributed and from which the original high bandwidth signal is recovered at the receiving node. During preliminary configuration, for example when selecting a subset of bearer channels from among a number of potential bearer channels, the bearer channels are chosen or are altered by signal processing to make the members of the subset perform similarly, thereby improving operations as compared to having the bearer channels bound to perform according to the performance of the least-performing member of the subset. | 11-10-2011 |
| 20110200322 | Flexible Branching Unit and System Including the Same - Fault tolerance may be achieved in a branched optical communication system such that a fault in one optical path may not affect optical signals coupled from a healthy optical path. In general, a flexible branching unit is configured, when adding and dropping channels, to select channels from a healthy path and not from the faulty path (e.g., a trunk path or a branch path) to prevent non-uniform channel loading on the trunk path after the branching unit. In this manner, a fault detected on the trunk path may not affect signals from the branch path and a fault detected on the branch path may not affect signals from the trunk path, thereby providing fault tolerance. A flexible branching unit may also be capable of adjusting the number and selection of channels that are added and dropped at the branching unit. | 08-18-2011 |
| 20110188803 | COUPLING MULTIPLE CONDUCTOR UNDERSEA OPTICAL CABLES TO AN UNDERSEA DEVICE WITH AN ISOLATED BYPASS CONDUCTIVE PATH ACROSS THE UNDERSEA DEVICE - A multiple conductor optical cable may be coupled to an undersea device, such as a cable joint, branching unit, or repeater, with one or more isolated bypass conductive paths being provided across the undersea device. At least one conductor may be terminated within a housing of the undersea device and at least one conductor may be coupled to a conductive bridge member that provides the isolated bypass conductive path across the device. Multiple conductor optical cables may be coupled to undersea devices in optical networks using independent power paths, for example, to deliver power to different powered components at different voltage potentials. | 08-04-2011 |
| 20110026925 | Hybrid Optical Add-Drop Multiplexing Network and Wavelength Allocation for the Same - An optical add-drop network and wavelength allocation for the same wherein the system bandwidth is separated into a dedicated channel band and re-used channel bands, separated by guard bands, to allocate terminal connections to achieve a minimum number of re-used channel bands for the desired terminal connectivities. | 02-03-2011 |
| 20100290786 | Branching Configuration Including Separate Branching Unit and Predetermined Wavelength Filter Unit and System and Method Including the Same - In general, a branching configuration used in a wavelength division multiplexed (WDM) optical communication system includes a branching unit (BU) and a separate predetermined wavelength filter (PWF) unit. The PWF unit may include wavelength selective elements (e.g., filters) for providing a desired wavelength allocation and may also include optical connections (e.g. optical couplers) for coupling the allocated wavelengths between trunk and branch paths in the WDM system. The PWF unit is physically separate from an associated BU but coupled adjacent the BU. | 11-18-2010 |
| 20100232809 | Detection of Data in Signals with Data Pattern Dependent Signal Distortion - A detection system and method may be used to detect data transmitted in a signal with data pattern dependent signal distortion. In general, a detection system and method compares samples of a received signal with stored samples of distorted signals associated with known data patterns and selects the known data patterns that correspond most closely with the samples of the received signal. The detection system and method may thus mitigate the effects of data pattern dependent signal distortion. | 09-16-2010 |
| 20100232805 | Local Oscillator Frequency Offset Compensation in a Coherent Optical Signal Receiver - A system and method implementing dual stage carrier frequency offset compensation (FOC) in a coherent receiver for an optical communication system. In the first stage, a feed forward FOC function compensates for relatively slowly drifting frequency offsets. In a second stage, a decision-feedback FOC function compensates for relatively quickly drifting frequency offsets. The feed forward frequency offset compensation may be implemented with a feed forward carrier phase estimation function and the decision-feedback frequency offset compensation may be implemented with a decision-feedback carrier phase estimation function. | 09-16-2010 |
| 20100232797 | Detection of Data in Signals with Data Pattern Dependent Signal Distortion - A detection system and method may be used to detect data transmitted in a signal with data pattern dependent signal distortion such as intersymbol interference. In general, a detection system and method compares samples of a received signal with stored samples of distorted signals associated with known data patterns and selects the known data patterns that correspond most closely with the samples of the received signal. The detection system and method may thus mitigate the effects of data pattern dependent signal distortion. | 09-16-2010 |
| 20100232796 | Data Pattern Dependent Distortion Compensation in a Coherent Optical Signal Receiver - A distortion compensation system and method may be used to compensate for data pattern dependent signal distortion in a signal received in a coherent optical signal receiver. In general, the distortion compensation system and method compares a received signal field with stored distorted signal waveforms associated with known data patterns and selects a compensation value associated with the distorted signal waveform that corresponds most closely with the received signal field. The distortion compensation system and method compensates the received signal using the selected compensation value and thus mitigates the effects of data pattern dependent signal distortion. | 09-16-2010 |
| 20100232788 | Dual Stage Carrier Phase Estimation in a Coherent Optical Signal Receiver - A system and method implementing dual stage carrier phase estimation (CPE) in a coherent receiver for an optical fiber communication system. In the first stage, a feed-forward CPE is implemented to make an initial carrier phase estimation of a training sequence. The initial carrier phase estimation is coupled to the second stage which implements a decision-feedback CPE. After a training period, accurate bit decision for system traffic can be achieved using the decision-feedback CPE. | 09-16-2010 |