Abstract: The present invention is directed to data communication system and methods. More specifically, various embodiments of the present invention provide a communication interface that is configured to transfer data at high bandwidth using nDSQ format(s) over optical communication networks. In certain embodiments, the communication interface is used by various devices, such as spine switches and leaf switches, within a spine-leaf network architecture, which allows large amount of data to be shared among servers.

Abstract: A method and structure for a coherent optical receiver device. Timing recovery (TR) is implemented after channel dispersion (i.e., chromatic dispersion (CD) and polarization mode dispersion (PMD)) compensation blocks. This architecture provides both improves performance and reduces power consumption of the device. Also, a TR loop is provided, enabling computing, by an error evaluation module, a first sampling phase error (SPE) and computing, by a timing phase information (TPI) module coupled to the error evaluation module, a second SPE from a plurality of CD equalizer taps PMD equalizer taps. The first and second SPE are combined into a total phase error (TPE) in a combining module, and the resulting TPE is filtered by a timing recovery (TR) filter coupled to an interpolated timing recovery (ITR) module and the combining module. The ITR module then synchronizes an input signal of the coherent optical receiver according to the TPE.

Abstract: A method and structure for tap centering in a coherent optical receiver device. The center of gravity (CG) of the filter coefficients can be used to evaluate a proper convergence of a time-domain adaptive equalizer. However, the computation of CG in a dual-polarization optical coherent receiver is difficult when a frequency domain (FD) adaptive equalizer is adopted. In this case, the implementation of several inverse fast-Fourier transform (IFFT) stages is required to back time domain impulse response. Here, examples of the present invention estimate CG directly from the FD equalizer taps and compensate for an error of convergence based off of the estimated CG. This estimation method and associated device architecture is able to achieve an excellent tradeoff between accuracy and complexity.

Abstract: A surface grating coupler for polarization splitting or diverse includes a planar layer and an array of scattering elements arranged in the planar layer at intersections of a first set of concentric elliptical curves crossing with a second set of concentric elliptical curves rotated proximately 90 or 180 degrees to form a two-dimensional (2D) grating. Additionally, the grating coupler includes a first waveguide in double-taper shape and a second waveguide in double-taper shape respectively for split or diverse an incident light into the 2D grating into two output light to two output ports with a same (either TE or TM) polarization mode or one output port with TE polarization mode and another output port with TM polarization mode. The polarization diverse grating coupler is required to test multiple polarization sensitive photonics components and can be used with other single polarization grating coupler via a fiber array to perform wafer-level testing.

Abstract: A method of operating a computer network system configured with disaggregated inputs/outputs. This system can be configured in a leaf-spine architecture and include a router coupled to a network source, a plurality of core switches coupled to the router, a plurality of aggregator switches coupled to each of the plurality of core switches, and a plurality of rack modules coupled to each of the plurality of aggregator switches. Each of rack modules can include an I/O appliance with a downstream aggregator module, a plurality of server devices each with PCIe interfaces, and an upstream aggregator module that aggregates each of the PCIe interfaces. A high-speed link can be configured between the downstream and upstream aggregator modules via aggregation of many serial lanes to provide reliable high speed bit stream transport over long distances, which allows for better utilization of resources and scalability of memory capacity independent of the server count.

Abstract: A compact optical transceiver formed by hybrid multichip integration. The optical transceiver includes a Si-photonics chip attached on a PCB. Additionally, the optical transceiver includes a first TSV interposer and a second TSV interposer separately attached nearby the Si-photonics chip on the PCB. Furthermore, the optical transceiver includes a driver chip flip-bonded partially on the Si-photonics chip through a first sets of bumps and partially on the first TSV interposer through a second sets of bumps. Moreover, the optical transceiver includes a transimpedance amplifier module chip flip-bonded partially on the Si-photonics chip through a third sets of bumps and partially on the second TSV interposer through a fourth set of bumps.

Abstract: A photonic transceiver apparatus in QSFP package. The apparatus includes a case having a base member, two partial side members, and a lid member to provide a spatial volume with an opening at a back end of the base member. Additionally, the apparatus includes a PCB, installed inside the spatial volume over the base member having a pluggable electrical connector at the back end. Further, the apparatus includes multiple optical transmitting devices in mini-transmit-optical-sub-assembly package, each being mounted on a common support structure and having a laser output port in reversed orientation toward the back end. Furthermore, the apparatus includes a silicon photonics chip, including a fiber-to-silicon attachment module, mounted on the PCB and coupled to a modulation driver module and a trans-impedance amplifier module. Moreover, the apparatus includes a pair of optical input/output ports being back connected to the fiber-to-silicon attachment module.

Abstract: An optical module processes first FEC (Forward Error Correction) encoded data produced by a first FEC encoder. The optical module has a second FEC encoder for further coding a subset of the first FEC encoded data to produce second FEC encoded data. The optical module also has an optical modulator for modulating, based on a combination of the second FEC encoded data and a remaining portion of the first FEC encoded data that is not further coded, an optical signal for transmission over an optical channel. The second FEC encoder is an encoder for an FEC code that has a bit-level trellis representation with a number of states in any section of the bit-level trellis representation being less than or equal to 64 states. In this manner, the second FEC encoder has relatively low complexity (e.g. relatively low transistor count) that can reduce power consumption for the optical module.

Abstract: A packaged transmitter device includes a base member comprising a planar part mounted with a thermoelectric cooler, a transmitter, and a coupling lens assembly, and an assembling part connected to one side of the planar part. The device further includes a circuit board bended to have a first end region and a second end region being raised to a higher level. The first end region disposed on a top surface of the planar part includes multiple electrical connection patches respectively connected to the thermoelectric and the transmitter. The second end region includes an electrical port for external connection. Additionally, the device includes a cover member disposed over the planar part. Furthermore, the device includes a cylindrical member installed to the assembling part for enclosing an isolator aligned to the coupling lens assembly along its axis and connected to a fiber to couple optical signal from the transmitter to the fiber.

Abstract: An integrated compact light engine configured in a on-board in-package optics assembly. The compact light engine includes a single substrate to integrate multiple optical-electrical modules. Each optical-electrical module includes an integrated optical transceiver based on silicon-photonics platform, in which a transmit path configured to output four light signals centered at four CWDM wavelengths and from four laser devices and to modulate the four light signals respectively by four modulators driven by a driver chip and to deliver a multiplexed transmission light. A receive path includes a photodetector to detect four input signals demultiplexed from an incoming light and a trans-impedance amplifier chip to process electrical signals converted from the four input signals detected. A multi-channel light engine is formed by co-integrating or co-mounting a switch device with multiple compact light engines on a common substrate member to provide up to 51.

Abstract: The present invention relates to telecommunication techniques and integrated circuit (IC) devices. In a specific embodiment, the present invention provides a laser deriver apparatus that includes a main DAC section and a mini DAC section. The main DAC section processes input signal received from a pre-driver array and generates an intermediate output signal. The mini DAC section provides a compensation signal to reduce distortion of the intermediate output signal. The intermediate output signal is coupled to output terminals through a cascode section and/or a T-coil section. There are other embodiments as well.

Abstract: The present invention relates to data communication systems and methods thereof. More specifically, embodiments of the present invention provide a data transmission method. Data are encoded with staircase encoder, and staircase coded blocks are first interleaved then combined into outer code frames. Code frames additionally include sync words and padding bits. A second interleaving is applied to the bits of the code frames, and Hamming encoding is performed on the output of the second interleaver. Hamming codewords are Gray-mapped to dual-polarized quadrature-amplitude-modulation (DP-QAM) symbols, and a third interleaving of the symbols from a set of successive Hamming codewords is performed. Pilot symbols are inserted periodically into the stream of DP-QAM symbols. There are other embodiments as well.

Abstract: A circuit and method for mitigating multi-path interference in direct detection optical systems is provided. Samples of an optical signal having a pulse amplitude modulated (PAM) E-field are processed by generating a PAM level for each sample. For each sample, the sample is subtracted from the respective PAM level to generate a corresponding error sample. The error samples are lowpass filtered to produce estimates of multi-path interference (MPI). For each sample, one of the estimates of MPI is combined with the sample to produce an interference-mitigated sample.

Abstract: Methods of operating an optical communication system in coherent optical transmissions for metro applications. Relative to conventional solutions, the optical communication system can be implemented with reduced cost and can operate with reduced power consumption, while maintaining high data rate performance (e.g., 100G). Furthermore, a programmable transceiver enables compatibility with a range of different types of optical networks having varying performance and power tradeoffs. In one embodiment, the optical communication system uses 100 Gb/s dual-polarization 16-point quadrature amplitude modulation (DP-16QAM) with non-linear pre-compensation of Indium Phosphide (InP) optics for low power consumption.

Abstract: Apparatus and method for digital signal constellation transformation are provided herein. In certain configurations, an integrated circuit includes an analog front-end that converts an analog signal vector representing an optical signal into a digital signal vector, and a digital signal processing circuit that processes the digital signal vector to recover data from the optical signal. The digital signal processing circuit generates signal data representing a signal constellation of the digital signal vector. The digital signal processing circuit includes an adaptive gain equalizer that compensates the signal data for distortion of the signal constellation arising from biasing errors of optical modulators used to transmit the optical signal.

Abstract: The present invention is directed to electrical circuits. and more specially, inductor designs that reduce on-chip electromagnetic coupling in certain applications. In a specific embodiment, the present invention provides an inductor that includes coils that are configured to generate magnetic fields of opposite polarities. The electromagnetic fields generated by the inductor coils substantially cancel out with each other, thereby minimizing parasitic inductance of the inductor and reducing interference with operations of other components in an integrated circuit. There are other embodiments as well.

Abstract: The present invention includes an integrated system-on-chip device configured on a substrate member. The device has a data input/output interface provided on the substrate member and configured for a predefined data rate and protocol. The device has an input/output block provided on the substrate member and coupled to the data input/output interface. The input/output block comprises a SerDes block, a CDR block, a compensation block, and an equalizer block. The SerDes block is configured to convert a first data stream of N having a first predefined data rate at a first clock rate into a second data stream of M having a second predefined data rate at a second clock rate. The device has a driver module provided on the substrate member and coupled to a signal processing block, and a driver interface provided on the substrate member and coupled to the driver module and a silicon photonics device.

Abstract: The present invention is directed to communication systems and methods. In a specific embodiment, the present invention provides an optical receiver that receives a data stream from an optical transmitter. The optical receiver determines a histogram contour parameter using the data stream and inserts the histogram contour parameter into a back-channel data segment, which is then transmitted to the optical transmitter. The optical transmitter changes its data transmission setting based on the histogram contour parameter. There are other embodiments as well.

Abstract: The present invention is directed to communication systems and electrical circuits. More specifically, an embodiment of the present invention provides a termination circuit that includes a programmable gain attenuation section, a T-coil section, and a termination resistor. The characteristic resistance of the programmable gain attenuation section matches the resistance of the termination resistor. There are other embodiments as well.

Abstract: A silicon optical modulator is fabricated to have a multi-slab structure between the contacts and the waveguide, imparting desirable performance attributes. A first slab comprises dopant of a first level. A second slab adjacent to (e.g., on top of) the first slab, comprises a doped region proximate to a contact, and an intrinsic region proximate to the waveguide. The parallel resistance properties and low overlap between the highly doped silicon and optical mode pigtail afforded by the multi-slab configuration, allow the modulator to operate with reduced optical losses and at a high speed. Embodiments may be implemented in a Mach-Zehnder interferometer or in micro-ring resonator modulator configuration.