Abstract: The invention comprises distribution point unit (DPU) including a host for a GPON ONU/ONT module, CPU system-on-chip (SoC) providing a DPU and traffic management, a reverse power harvester and a high speed electrical (HSE) module and the DPU receiving optical signals via the GPON ONU/ONT module and converting to electrical signals and the HSE module transmitting electrical signals via a twisted pair or coaxial cable to a customer premises equipment (CPE) within a home or building and the reverse power harvester receiving power from the HSE module and the GPON ONU/ONT and HSE modules are pluggably mateable to the DPU.

Abstract: An optical mirror diversity receiver for a visible light communication system is provided with an array of photodiodes each having an optical-signal-receiving area, with a mirror positioned between an adjacent pair of photodiodes to preferentially redirect light toward one of the photodiodes while also blocking light that would otherwise be received at the photodiode. An angle-aided mirror diversity receiver is also provided with surfaces of the photodiodes aligned relative to the mirror to yield reductions in correlation.

Abstract: Provided are a next generation in-building relay system and method. The system includes: a 5G signal providing unit configured to down-convert a millimeter wave radio frequency signal to an intermediate frequency signal; a 5G master hub unit configured to convert the intermediate frequency signal into a radio over fiber (RoF) signal and transmit the RoF signal; an optical coupling unit configured to couple a digital optical signal output from a master hub unit and the analog optical signal output from the 5G master hub unit and transmit the coupled signal to an optical cable; and an optical distribution unit configured to separate the digital optical signal and the analog optical signal from the coupled signal, transmit the digital optical signal to a remote optical relay unit, and transmit the analog optical signal to distributed remote units.

Abstract: According to an example aspect of the present invention, there is provided an apparatus comprising a first and a second polarization beam splitter-rotator (140, 142), together arranged to split two incoming polarization encoded qubits into four first optical modes, the apparatus being configured to align polarizations of the four first optical modes, an interferometer stage (150) configured to obtain, from the four first optical modes, four second optical modes, and four detectors (160) arranged to receive at least one of the four second optical modes.

Abstract: By determining an alignment point for a photonic element in a substrate of a given material; applying, via a laser aligned with the photonic element according to the alignment point, an etching pattern to the photonic element to produce a patterned region and an un-patterned region in the photonic element, wherein applying the etching pattern alters a chemical bond in the given material for the patterned region of the photonic element that increases a reactivity of the given material to an etchant relative to a reactivity of the un-patterned region, and wherein the patterned region defines an engagement feature in the un-patterned region that is configured to engage with a mating feature on a Photonic Integrated Circuit (PIC); and removing the patterned region from the photonic element via the etchant, various systems and methods may make use of laser patterning in optical components to enable alignment of optics to chips.

Abstract: An optical transmission device according to the present disclosure includes: an optical connector connection unit to which a connector unit of an optical cable is attached; a light emitting end configured to emit light to transmit an optical signal via the optical cable, and configured to radiate light to a reflection surface of the connector; and a driving unit configured to drive the reflection surface to refract the light radiated to the reflection surface toward an optical transmission path of the optical cable through refraction on the reflection surface in the case where the connector unit is attached in first orientation, and configured to drive the reflection surface to refract the light radiated to the reflection surface toward the optical transmission path of the optical cable through refraction on the reflection surface in the case where the connector unit is connected in second orientation that is different from the first orientation.

Abstract: Methods and systems for waveguide delay based equalization with optical splitting in optical communication may include an optoelectronic circuit comprising an input waveguide, a directional coupler, an optical delay, photodetectors, a current mirror, and a transimpedance amplifier. The optoelectronic circuit may receive an input optical signal via the input waveguide, split the input optical signal into first and second output signals using the directional coupler, delay the first output signal using the optical delay, convert the delayed first output signal to a first electrical signal using a first photodetector, convert the second output signal to a second electrical signal using a second photodetector, amplify the second electrical signal using the current mirror, and sum the first and second electrical signals at inputs of the transimpedance amplifier to generate an output voltage.

Abstract: A functional optical device applicable to a coherent optical communication system as a front end device is disclosed. The functional optical device includes a pair of light-receiving elements of a type of waveguide photodiode (PD), a pair of signal pads, a pair of ground pads, a bias pad, and a substrate that monolithically integrates those elements thereon. The light-receiving elements generate a photocurrent complementary to each other in respective anodes thereof; while, receive biases through the bias pad common to the light-receiving elements. Those pads are disposed along an edge of the substrate such that the signal pads put the bias pads therebetween, and the ground pads put the signal pads and the bias pad therebetween.

Abstract: A multi-channel receiver optical subassembly (ROSA) including at least one sidewall receptacle configured to receive and electrically isolate an adjacent multi-channel transmitter optical subassembly (TOSA) is disclosed. The multi-channel ROSA includes a housing with at least first and second sidewalls, with the first sidewall being opposite the second sidewall and including at least one sidewall opening configured to fixedly attach to photodiode assemblies. The second sidewall includes at least one sidewall receptacle configured to receive at least a portion of an optical component package, such as a transistor outline (TO) can laser package, of an adjacent multi-channel TOSA, and provide electrical isolation between the ROSA housing and the TOSA within an optical transceiver. The sidewall receptacle can include non-conductive material in regions that directly or otherwise come into close proximity with the optical component package of the adjacent TOSA.

Abstract: A polarization reducing apparatus includes a separating unit configured to separate input light into components having polarization directions orthogonal to each other; a winding waveguide of silicon formed on a silicon substrate in a winding manner, the winding waveguide transmitting a first component among the components separated by the separating unit; an optical path configured to have a shorter optical path length than the winding waveguide, the optical path transmitting a second component among the components separated by the separating unit; a combining unit configured to combine the first component and the second component; and an output unit configured to output light consisting of the first component and the second component combined by the combining unit.

Abstract: There is provided a receiver optical module including a photodetector having a plurality of channels, a capacitor disposing block formed on an upper portion of the photodetector, a plurality of capacitors formed on the capacitor disposing block, and an electrical wiring configured to connect the plurality of capacitors to electrodes of a plurality of channels of the photodetector, wherein the plurality of capacitors are formed on the capacitor disposing block such that distance between the capacitors and the electrodes of the corresponding channels are the same. Distortion and loss of signal characteristics of high frequency can be reduced and quality of a signal can be enhanced.

Abstract: An optical modulator is disclosed, in which a MMI couplers are used for input signal splitting for branching into individual Mach-Zehnder interferometers, as well as for branching and combining from individual Mach-Zehnder waveguides. MMI couplers, splitters, and combiners may be cascaded and combined with single-mode Y-splitters and combiners to provide modulators of various types, including dual polarization, quadrature phase Mach-Zehnder interferometer base optical modulators.

Abstract: A multi-chip module (MCM) is described. This MCM includes two substrates that are passively self-assembled on another substrate using hydrophilic and hydrophobic materials on facing surfaces of the substrates and liquid surface tension as the restoring force. In particular, regions with a hydrophilic material on the two substrates overlap regions with the hydrophilic material on the other substrate. These regions on the other substrate may be surrounded by a region with a hydrophobic material. In addition, spacers on a surface of at least one of the two substrates may align optical waveguides disposed on the two substrates, so that the optical waveguides are coplanar. This fabrication technique may allow low-loss hybrid optical sources to be fabricated by edge coupling the two substrates. For example, a first of the two substrates may be a III/V compound semiconductor and a second of the two substrates may be a silicon-on-insulator photonic chip.

Abstract: A multi-chip module (MCM) is described. This MCM includes two substrates that are passively self-assembled on another substrate using hydrophilic and hydrophobic materials on facing surfaces of the substrates and liquid surface tension as the restoring force. In particular, regions with a hydrophilic material on the two substrates overlap regions with the hydrophilic material on the other substrate. These regions on the other substrate may be surrounded by a region with a hydrophobic material. In addition, spacers on a surface of at least one of the two substrates may align optical waveguides disposed on the two substrates, so that the optical waveguides are coplanar. This fabrication technique may allow low-loss hybrid optical sources to be fabricated by edge coupling the two substrates. For example, a first of the two substrates may be a III/V compound semiconductor and a second of the two substrates may be a silicon-on-insulator photonic chip.

Abstract: A frequency modulation signal demodulator includes: an optical signal that has a wavelength, a frequency modulation signal being superimposed onto the optical signal; an optical filter that inputs the optical signal and has a central wavelength of a pass band at a wavelength that is shifted from a central wavelength of a spectrum of the optical signal and that is set to allow the pass band to be located at one portion of the spectrum; and an asymmetry optical interferometer that demodulates the frequency modulation signal by splitting light which has passed through the optical filter, delaying different time between split lights, and interfering the split lights.

Abstract: An optical communications system includes a first plurality of optical components having optical ports, a second plurality of optical components having optical ports and an optical cross-connect. The optical cross-connect includes a block of a single continuous construction and material having a first side adjacent the first optical components and a second side adjacent the second optical components, and a plurality of non-intersecting, continuous waveguides formed within the block and extending from the first side of the block to the second side of the block. The refractive index of each waveguide is different than the surrounding material of the block, and each waveguide changes direction at least once within the block. The waveguides are optically aligned with the optical ports of the first optical components at the first side of the block and with the optical ports of the second optical components at the second side of the block.

Abstract: An optical receiver circuit includes a polarization beam splitter configured to split input signal light into two different polarized wave components; two variable optical attenuators configured to respectively adjust attenuation of and output the signal light split by the polarization beam splitter according to polarization state; and a single planar optical waveguide on which the polarization beam splitter and the two variable optical attenuators are disposed.

Abstract: An optical communication device includes a substrate, a photoelectric element for emitting/receiving optical signals, a driver chip for driving the photoelectric, and a light waveguide for transmitting optical signals. The substrate defines a through fixing hole. The photoelectric element and the driver chip are electrically connected to the substrate. The photoelectric element includes a base portion and an optical portion formed on the base portion. The optical portion includes an optical surface serving as a light emergent/incident surface, the optical surface faces toward the substrate, and the optical portion is aligned with the fixing hole. An end of the light waveguide is inserted and fixed into the fixing hole and is optically aligned with the optical portion.

Abstract: Optical devices are disclosed consisting of optical chips (planar lightwave circuits) which have optically symmetric or matching designs and properties and optical components which create asymmetry in the optical devices. The devices find application in detection in coherent and non-coherent optical communications systems.

Abstract: An optical transmission-reception system includes: a light-emitting element having a first semiconductor multilayer structure with a ring- or disk-like shape and generating a first optical signal and a second optical signal rotating in a direction opposite to the first optical signal; a first optical waveguide optically coupled with the light-emitting element and propagating the first optical signal; a second optical waveguide optically coupled with the light-emitting element and propagating the second optical signal; and a light-receiving element having a second semiconductor multilayer structure with a ring- or disk-like shape, optically coupled with the first and second optical waveguides, and optically receiving the first and second optical signals.

Abstract: A format for modified IRIB-G time code, with added message fields while preserving pulse width coding rule of the standard IRIG-B time code, having a time interval field for carrying time interval between the local time signal and a received time signal, and a user-defined or padded field for carrying user-defined time and/or control messages. An encoding and a decoding methods and devices for high-precision time transfer, where the modified IRIG-B time code carries more messages, and enabling transmission of timing messages and testing messages of two-way time comparison via a single message channel at the same time, which reduces fluctuation due to encoding and decoding manipulation and correlation with working frequencies via exact synchronization between the on-times of the output encoded time code and the transmitted time signal, and between the on-times of the output decoded time signal and the input time code, and improves precision of time transfer.

Abstract: A sensing apparatus includes: a broadband optical source; a first pseudorandom number generator generating a first pseudorandom number code string to modulate the broadband optical source; at least one sensor reflecting an output of the first pseudorandom number generator at a wavelength corresponding to a center wavelength thereof when the output of the first pseudorandom number generator is inputted; a wavelength-time converter converting an output of the sensor by wavelength-time conversion; a second pseudorandom number generator generating a second pseudorandom number code string which is different in frequency from and is the same in bit length and code string as the first pseudorandom number code string; a mixer mixing an output signal of the wavelength-time converter with an output signal of the second pseudorandom number generator; and an integrator integrating an output of the mixer.

Abstract: An optical communication system, a transmitter, a receiver, and methods of operating the same are provided. In particular, a transmitter is disclosed as being configured to encode optical signals in accordance with a multi-level coding scheme. The receiver is configured to provide receive and decode to the optical signals received from the transmitter. One or both of the receiver and transmitter are configured to compensate for non-idealities or non-linearities introduced into the communication system by optical components of the system.

Abstract: Disclosed is a multi-channel receiver optical sub assembly. The a multi-channel receiver optical sub assembly includes: a multi-channel PD array, in which a plurality of photodiodes (PDs) disposed on a first capacitor, and including receiving areas disposed at centers thereof and anode electrode pads arranged in an opposite direction at an angle of 180 degrees based on the receiving areas between the adjacent PDs is monolithically integrated; a plurality of transimpedance amplifiers (TIAs) arranged on a plurality of second capacitors, respectively, and connected with the anode pads of the respective PDs through wire bonding; a submount on which the first capacitor.

Abstract: A low voltage photodetector structure including a semiconductor device layer, which may be Ge, is disposed over a substrate semiconductor, which may be Si, for example within a portion of a waveguide extending laterally within a photonic integrated circuit (PIC) chip. In exemplary embodiments where the device layer is formed over an insulator layer, the insulator layer is removed to expose a surface of the semiconductor device layer and a passivation material formed as a replacement for the insulator layer within high field regions. In further embodiments, controlled avalanche gain is achieved by spacing electrodes in a metal-semiconductor-metal (MSM) architecture, or complementary doped regions in a p-i-n architecture, to provide a field strength sufficient for impact ionization over a distance not significantly more than an order of magnitude greater than the distance that a carrier must travel so as to acquire sufficient energy for impact ionization.

Abstract: In part, aspects of the invention relate to methods, apparatus, and systems for intensity and/or pattern line noise reduction in a data collection system such as an optical coherence tomography system that uses an electromagnetic radiation source and interferometric principles. In one embodiment, the noise is intensity noise or line pattern noise and the source is a laser such as a swept laser. One or more attenuators responsive to one or more control signals can be used in conjunction with an analog or digital feedback network in one embodiment.

Abstract: In at least same examples, a communication device includes a photo-diode to convert an optical signal into an electrical current and an open-gain trans-impedance amplifier to amplify the electrical current. The communication device also includes a transmission line between the photo-diode and the open-gain trans-impedance amplifier. The open-gain trans-impedance amplifier includes a programmable input impedance that has been matched to an impedance of the transmission line.

Abstract: An optical module for receiving light according to a digital coherent optical transmission scheme includes two optical fibers, and a monitor PD. The optical signal processing circuit includes a substrate, an optical waveguide layer made up of a core and a clad layer stacked on top of the substrate, and fixtures stacked on top of the clad layer on the one end, and is provided with a light shield member which spans the substrate, the clad layer, and the edge face of the fixture on the edge face of the optical signal processing circuit that faces the monitor PD, and which includes an aperture unit aligned with the given site where the diverted signal light is output.

Abstract: An optical receiver including a waveguide substrate including a first waveguide that transmits a main signal beam, a second waveguide that transmits a monitoring beam that has branched from the main signal beam, and a third waveguide that transmits an amplification beam to amplify the main signal beam; a light receiving device array including, integrally formed to the same substrate, a first light receiving device that detects the main signal beam and a second light receiving device that detects the monitoring beam; and a case that houses the waveguide substrate and the light receiving device array. The first light receiving device faces toward an end of the first waveguide, and the second light receiving device faces toward an end of the second waveguide.

Abstract: There is provided an optical receiver. The optical receiver includes a board to be coupled with an optical transmission line array, an optical diode array disposed on the board, and the optical diode array including a plurality of photo diodes each of which receives light from a corresponding optical transmission line in the optical transmission array. Further bias suppliers, conversion circuits, and capacitors are provided on the board or a real side of the board. Each of the photo diodes includes a first electrode and second electrodes, the first electrode receives a bias voltage supplied by a bias supplier, a current signal flowing through the second electrode is converted by a conversion circuit into a voltage signal, and one end of a capacitor is coupled to the first electrode and the other is grounded.

Abstract: An optical field receiver comprises an optical branching circuit for branching a received optical multilevel signal into first and second optical signals, a first optical delayed demodulator for performing delayed demodulation on the first optical signal at a delay time T (T=symbol time), a second optical delayed demodulator for performing delayed demodulation on the second optical signal at the delay time T with an optical phase difference deviating from the first optical delayed demodulator by 90°, first and second optical receivers for converting each of the delayed demodulation signals representing x and y components of complex signals output from the first and second delayed demodulators into first and second electrical signals, and a field processing unit fort generating a first reconstructed signal representing an inter-symbol phase difference or a phase angle of a received symbol from the first and second electrical signals for each symbol time T.

Abstract: A polarization-insensitive optical receiver for demodulating a phase-modulated input optical signal is provided. The optical receiver includes successively a polarization splitter, a first and second interferometric modules including respective delay lines, and a plurality of detectors. The input optical signal is split into two substantially orthogonally-polarized components, which are launched along respective optical paths into the corresponding interferometric modules where they demodulated and subsequently recombined prior to being detected by the plurality of detectors. Advantageously, the optical receiver allows mitigating undesired discrepancies between the optical paths traveled by the two polarization components by arranging the respective delay lines of the interferometric modules into intertwined spiraling structures.

Abstract: A multi-channel optical waveguide receiver includes an optical input port; an optical branching unit; light-receiving elements having bias electrodes and signal electrodes; optical waveguides being optically coupled between the optical branching unit and the light-receiving elements; capacitors electrically connected between the bias electrodes and a reference potential, the capacitors and the bias electrodes being connected through interconnection patterns; and a signal amplifier including input electrodes. The optical branching unit, the light-receiving elements, the optical waveguides, and the capacitors are formed on a single substrate, the substrate having an edge extending in a first direction. The signal amplifier and the substrate are arranged in a second direction crossing the first direction. The input electrodes and the signal electrodes are arranged along the edge of the substrate.

Abstract: In a coherent optical receiver of an optical communications system, methods and systems for receiving a data signal x(t) modulated on an optical signal. A linearly polarized LO light is generated, which has a frequency of f1=f0±?f, where f0 is a frequency of a narrowband carrier of the optical signal, and ?f corresponds with a band-width fB of the data signal x(t). The LO light and a received light of the optical signal are heterodyned on a photodetector. An analog signal generated by the photodetector is low-pass filtered to generate a filtered signal, using a filter characteristic having a sharp cut-off at a frequency of ?f+nfB, where n is an integer multiple. An analog-to digital (A/D) converter samples the filtered signal at a sample rate of 2(?f+nfB) to generate a corresponding multi-bit digital sample stream. The multi-bit digital sample stream is digitally processed to recover respective In-Phase and Quadrature components of the received light of the optical signal.

Abstract: Methods, apparatus and systems for an optical system for data harvesting and pattern recognition. The system includes a mode locked laser for producing a comb of optical frequencies that is split into two identical combs, a wavelength division demultiplexer eparate the individual optical frequency components of one comb and modulates each optical frequency component with a different one of plural target objects. A second modulator modulates an input signal with the second comb and an optical splitter splits the modulated signal into plural optical frequency components each containing the input signal. An optical combiner simultaneously combines the components containing the real time signal with one of the components containing a target object to produce a temporally modulated interferogram, and a comparator simultaneously compares the two on a comb by comb basis using balanced differential detection to determine any of the plural target objects are found in the input signal.

Abstract: A particular method includes directing wave energy toward a collection region inside a collector by receiving the wave energy from outside the collector through an at least partially transparent portion of the collector and reflecting the wave energy toward the collection region using an at least partially reflective portion of the collector. The method also includes receiving the wave energy at a receiver disposed in the collection region.

Abstract: Provide an optical receiver module. The optical receiver module includes: an optical fiber array including a first optical fiber that delivers an optical signal and a second optical fiber that delivers a reference optical signal; a plate optical integrated circuit including first and second multi mode interference (MMI) optical isolators respectively receiving the optical signal and the reference optical signal through a plurality of first optical waveguides; and an optical detector array receiving two optical signals from each of the first and second MMI optical isolators through a plurality of second optical waveguides, wherein the optical detector array includes a plurality of third optical waveguides aligned to be connected to the other end of each of the plurality of second optical waveguides in one-to-one correspondence.

Abstract: A photodetector receiver circuit for an optical communication system includes an optical photodetector which receives optical signals and converts them into an electrical current. In one illustrative embodiment, a dynamic impedance module which switches the receiver circuit between a high impedance state and a low impedance state and a buffer stage which receives the electrical current and converts the electrical current into a voltage signal compatible with a digital circuit. A method for receiving an optical signal includes, receiving the optical signal and converting it into an electrical pulse train, switching a dynamic impedance module between a high impedance state and a low impedance state, transforming the electrical pulse train into an output voltage signal using a buffer stage, and receiving the output voltage signal by a digital circuit.

Abstract: Systems and methods of polarization demultiplexing are disclosed. One such method receives a transmitted polarization-multiplexed optical signal The polarization-multiplexed has multiple polarizations, each of which represents an independent data stream. The method converts the polarization-multiplexed optical signal to a corresponding polarization-multiplexed electrical signal. The method determines an inverse transformation matrix that meets an independent component analysis (ICA) criterion. The method applies the inverse transformation matrix to the polarization-multiplexed electrical signal, which produces a polarization-demultiplexed electrical signal. The method phase estimates the polarization-demultiplexed electrical signal to recover the data stream.

Abstract: An intelligent optical module to restart itself according to a command sent from the host system is disclosed. The optical module may distinguish the first state, where no optical signal is received, from the second state, where a substantial optical signal but unmodulated is received. The optical module is restarted when the second state appears with a preset pattern.

Abstract: In order to provide a high performance optical mixer having good yield, an optical mixer comprises: a first light branching means that branches a first input light into a plurality of first lights including a first output light and a second output light, and outputs the first lights; a second light branching means that branches a second input light into a plurality of second lights including a third output light and a fourth output light, and outputs the second lights; and a first light coupling and branching means and a second light coupling and branching means that couple the first and the third output lights and the second and the fourth output lights respectively, and branching the coupled lights into at least two, and outputting each of the branched lights as a coupled-and-branched light, wherein propagation paths for the third and the fourth output lights comprise widths that cause a prescribed optical path length difference to occur between the third and the fourth output lights, and propagation path l

Abstract: A particular method includes applying light pulses to an optical fiber and receiving backscattered light at a phase-sensitive optical time domain reflectometry (OTDR) device. The backscattered light includes portions of the applied light pulses that are backscattered by the optical fiber. The method also includes determining a difference between the backscattered light and a backscatter pattern associated with the optical fiber. The method also includes determining a communication signal encoded in the backscattered light based on the difference, where the communication signal is encoded in the backscattered light responsive to mechanical waves applied to the optical fiber at a location remote from the phase-sensitive OTDR device.

Abstract: A receiving device includes: an amplification fiber configured to include properties to amplify signal light when pumping light is supplied to the amplification fiber and to attenuate the signal light when the pumping light is stopped supplying to the amplification fiber; a receiver configured to receive the signal light output from the amplification fiber; a pumping light source configured to supply the pumping light to the amplification fiber; and a controller configured to control supplying and stopping of the pumping light from the pumping light source to the amplification fiber, so that a level of the signal light input to the receiver is contained within a dynamic range of the receiver.

Abstract: The invention relates to an optical fiber employable in an optical communication system using Raman amplification and adapted to improve OSNR and suppress bending loss at the same time, and the like. The optical fiber is a silica-based optical fiber having a depressed refractive index profile constituted by at least a core, an inner cladding having a low refractive index, and an outer cladding, an effective area Aeff of 110 ?m2 or more at the wavelength of 1550 nm, and a fiber cutoff wavelength ?c of 1.3 ?m or more but 1.53 ?m or less. The depressed refractive index profile is designed such that the ratio Ra(=2b/2a) of the diameter of the inner cladding to the diameter of the core is 2.5 or more but 3.5 or less and that the relative refractive index difference ?? of the inner cladding with respect to the outer cladding is at least the relative refractive index difference ??min where the bending loss at the wavelength for use is minimized but not exceeding (??min+0.06) %.

Abstract: A system configured to maintain a consistent local-oscillator-power-to-primary-signal-power ratio (LO/SIG ratio).

Abstract: To reduce a size of an optical communication module.<br></br> There is provided an optical communication module 1, which includes a photoelectric conversion element package 10 to which a photoelectric conversion element 12 of either one of a light emitting element and a light receiving element is fitted so as to face one side 11a of a resin base 11, and an optical fiber coupler 20 having a light transmission hole 20c for coupling with an optical fiber in cylindrical portions 20a and 20b and mounted on the one side 11a of the resin base 11, where the photoelectric conversion element 12 and the light transmission hole 20c formed in the optical fiber coupler 20 are assembled aligned with an optical axis K.

Abstract: A method and system for optoelectronic receivers utilizing waveguide heterojunction phototransistors (HPTs) integrated in a CMOS SOI wafer are disclosed and may include receiving optical signals via optical fibers operably coupled to a top surface of the chip. Electrical signals may be generated utilizing HPTs that detect the optical signals. The electrical signals may be amplified via voltage amplifiers, or transimpedance amplifiers, the outputs of which may be utilized to bias the HPTs by a feedback network. The optical signals may be coupled into opposite ends of the HPTs. A collector of the HPTs may comprise a silicon layer and a germanium layer, a base may comprise a silicon germanium alloy with germanium composition ranging from 70% to 100%, and an emitter including crystalline or poly Si or SiGe. The optical signals may be demodulated by communicating a mixer signal to a base terminal of the HPTs.

Abstract: Technology for detecting an optical data signal carried in a combined optical signal that comprises a carrier optical signal modulated by the optical data signal and also comprises ASE noise. The proposed optical data detector/receiver is provided with an SHG device adapted to generate a second harmonic optical signal of the carrier optical signal modulated by the data signal. In the signal, generated by the SHG, the ASE noise will be essentially reduced.

Abstract: An apparatus comprising an optical receiver configured to receive an optical signal, and a combined level and clock recovery circuit coupled to the optical receiver and configured to update a signal threshold and a clock phase substantially simultaneously. Also included is an apparatus comprising at least one processor configured to implement a method comprising recognizing reception of a signal, and adjusting a threshold and a clock phase associated with the signal using a rising time for the signal and a falling time for the signal. Also included is a method comprising receiving a signal, and adjusting a threshold level of the signal to establish level recovery using a clock recovery scheme.

Abstract: Tunable resonator systems and methods for tuning resonator systems are disclosed. In one aspect, a resonator system includes an array of resonators disposed adjacent to a waveguide, at least one temperature sensor located adjacent to the array of resonators, and a resonator control electronically connected to the at least one temperature sensor. Each resonator has a resonance frequency in a resonator frequency comb and channels with frequencies in a channel frequency comb are transmitted in the waveguide. Resonance frequencies in the resonator frequency comb are to be adjusted in response to ambient temperature changes detected by the at least one temperature sensors to align the resonance frequency comb with the channel frequency comb.