Abstract: A plurality of inductors are connected in series between a load resistor and a first transistor, and a plurality of second transistors provided in parallel are connected to the plurality of inductors.

Abstract: An optical communication module which uses a single optical fiber to enable bidirectional communication or multiplexing communication is provided.

Abstract: The present invention provides a system, apparatus and method to improve the signal-to-noise ratio performance in receivers configured to receive differential data signals. According to various embodiments of the invention, a received differential signal is processed to consider both forward-looking and backward-looking error components to improve SNR performance, and ultimately the reach of the optical line system. Additional processing is provided to further enhance noise tolerance related to chromatic dispersion.

Abstract: A fiber optic connector release mechanism for releasing a transceiver module in a cage permanently mounted on a PCB is disclosed. The release mechanism includes a bail rotating a U-shaped flange through a two stage travel path to urge the bail forward in a slide path on the transceiver module. The release mechanism includes a boss disposed on one of the bail and the arm assembly and a dimple disposed on another of the bail and the arm assembly to secure the bail in a locked position. As the bail moves forward from the locked position, wedge elements at the end of arms extending rearward may contact locking tabs on the cage, forcing the locking tabs outward. As the locking tabs are forced outward, the shoulders of the transceiver module are released, and the transceiver module is free to slide out of the cage.

Abstract: A transmitter reduces or minimizes pulse narrowing. In one approach, an optical transmitter is designed to transmit data over an optical fiber at a specified data rate using on-off keying. The transmitter includes a pre-converter electrical channel and a limiting E/O converter. The pre-converter electrical channel produces a pre-converter signal that drives the limiting E/O converter. The pre-converter electrical channel is designed to reduce pulse narrowing in the pre-converter signal. In one implementation, the pre-converter electrical channel includes a pre-emphasis filter that is designed to minimize pulse width shrinkage.

Abstract: A digital signal processing optical transceiver includes: a reception front end for separating an optical reception signal from a communication path into a total of four channels including an I-channel and a Q-channel of an X-polarized wave component and an I-channel and a Q-channel of a Y-polarized wave component; and a digital signal processing unit for: performing signal point determination with respect to signals of the four channels; when there are only two signal points, selecting two channels including an I-channel component of an X-polarized wave and an I-channel component of a Y-polarized wave and performing signal processing thereon; and when there are four signal points, selecting the four channels including the I-channel component and a Q-channel component of the X-polarized wave and the I-channel component and a Q-channel component of the Y-polarized wave and performing the signal processing thereon.

Abstract: A floating heat sink device is provided that attaches to a cage in a floating configuration that enables the heat sink device to move, or “float”, as the parallel optical communications device secured to the cage moves relative to the cage. Because the heat sink device floats with movement of the parallel optical communications device, at least one surface of the parallel optical communications device maintains continuous contact with at least one surface of the heat sink device at all times. Ensuring that these surfaces are maintained in continuous contact at all times ensures that heat produced by the parallel optical communications device will be transferred into and absorbed by the floating heat sink device.

Abstract: In an optical transmission apparatus, an optical-to-electrical converter converts a received optical signal into an electrical signal, and an amplifier amplifies the resulting electrical signal. A plurality of analog-to-digital converters then convert the amplified electrical signal from analog form to digital form in a time-interleaved manner to produce digital outputs. When correcting the analog-to-digital converters, a controller varies the gain of the amplifier in such a way that a total amplitude or an average amplitude indicated by the digital outputs of the analog-to-digital converters will be equal to or greater than a specified threshold.

Abstract: An optical transmission apparatus for suppressing deterioration of transmission quality due to XPM in a wavelength division multiplexing optical communication system in which an intensity modulation optical signal and a phase modulation optical signal exist in a mixed form. The apparatus has an intensity inversion signal light output section which outputs light having an intensity pattern obtained by inverting intensity changes of the intensity modulation optical signal near a wavelength of the intensity modulation optical signal in arrangement on wavelength axis of optical wavelengths that can be multiplexed as a wavelength division multiplexed signal as intensity inversion signal light, and a wavelength division multiplexed optical signal output unit which wavelength-division-multiplexes the intensity modulation optical signal, the phase modulation optical signal and light from the intensity inversion signal light output section and outputs a wavelength division multiplexed optical signal.

Abstract: A fiber optic connector release mechanism is disclosed. The mechanism may be used to release a transceiver module housed in a cage that is permanently mounted on a printed circuit board. The release mechanism may include a cam mounted bail that rotates a U-shaped flange through a two stage travel path to urge the bail forward in a slide path on the transceiver module. As the bail begins to move forward, wedge elements at the end of a pair of slide arms extending rearward from the bail may contact locking tabs on the cage, forcing the locking tabs outward. As the locking tabs are forced outward, the shoulders of the transceiver module are released, and the transceiver module is free to slide out of the cage as the operator pulls on the bail.

Abstract: An optical transceiver calibration system and manufacturing method to fabricate a dual closed loop control transceiver are provided. The calibration system and method includes measuring an operating temperature and determining operational parameters based upon the operating temperature. The operational parameters may include, for example, a target power for transmitting a digital one, a target power for transmitting a digital zero, a modulation current, and a bias current. A bias may be added to the temperature to account for the difference between the temperature at the temperature sensor and the optical equipment. The operational parameters are preferably calculated independently of each other and are used as initial values during operating modes and allow the control loop to converge more quickly. The optics data is may be scanned electronically via bar code or some other electronic format prior to test. The software residing on the module then calibrates and configures the transceiver.

Abstract: The disclosure relates to optical fiber transmission systems, and in particular, pertains to the transceiver cards in an optical fiber transport system. In particular the disclosure teaches an improved transceiver card architecture that allows high density, flexibility and interchangeability of functionality.

Abstract: In one embodiment, an optical transmission system transmits data using a format according to which a data frame has two or more pilot-symbol blocks, each having a guard interval, and two or more payload-symbol blocks that are concatenated without a guard interval between them. The use of guard intervals in the pilot-symbol blocks helps the synchronization and channel-estimation procedures performed at a receiver of the optical transmission system to be robust in the presence of certain transmission impairments. The absence of guard intervals in the payload-symbol blocks helps to minimize the transmission overhead and thus achieve relatively high payload-data throughput.

Abstract: Disclosed herein is a bi-directional optical sub-assembly structured to reduce reflection noise. The bi-directional optical sub-assembly includes an optical fiber; a transmitter transmitting an optical transmit signal having passed through a 45° filter to the outside through the optical fiber, a receiver receiving an optical receive signal which is received from the outside through the optical fiber, is reflected by the 45° filter and passes through a 0° filter; a body encompassing a part of the optical fiber, a part of the transmitter and a part of the receiver; a cap housing encompassing a part of the transmitter and including an opening to provide a passage for the optical transmit signal from the transmitter to the optical fiber, and a filter holder having the 45° filter and the 0° filter attached thereon within the body.

Abstract: Techniques are provided for implementing a burst mode optical receiver capable of maintaining a stable gain profile in response to a burst signal. The optical receiver has a photodiode in balanced circuit configuration with a separate RF amplifier stage connected to each terminal of the photodiode. The two RF amplifier stages are coupled to biasing voltage sources that are inverted in comparison to the terminal connections and that, in some examples, each contain a field effect transistor (FET) that having a gate that is controlled in response to a sensed voltage. The burst mode optical receiver may be used in numerous applications, including optical line terminations (OLTs) in passive optical networks (PONs).

Abstract: A method, a device, and a system for realizing data transmission extension in a passive optical network (PON) are provided. Between a burst-mode clock and data recovery (BCDR) module and an electrical-optical (E/O) amplification module, the device includes a delimiter matching module and a preamble buffering and compensating module. The delimiter matching module is adapted to receive a data frame sent by the BCDR module and determine a location of a delimiter in the data frame. An optical-electrical (O/E) amplification module performs O/E conversion, amplification, and shaping on the data frame. The BCDR module then performs clock and data recovery processing on the data frame.

Abstract: A method and a device provide signal processing. The method contains the steps of separating a pilot signal from an analog signal, reducing or compensating a noise based on a local oscillator laser by demodulating the pilot signal, processing the demodulated pilot signal, and combining the processed demodulated pilot signal with the analog signal. Furthermore, a method for signal processing at a transmitter, according devices and a communication system are described.

Abstract: Methods and systems for an optical line termination including instructions stored on a computer-readable medium, the instructions including a digital diagnostic table, and a plurality of entries within the diagnostic table, wherein a first entry is associated with a first optical network unit, the first entry including at least one setting for performing burst mode digital diagnostic processes using a first burst mode transmission received from the first optical network unit.

Abstract: In an optical access system, the OLT includes a CP inserting unit that inserts a CP into a downlink signal; a CP removing unit that removes a CP from an uplink signal received from the ONU; and an FFT unit, an EQ unit, and an inverse FFT unit that perform equalization on the uplink CP-removed signal according to a frequency domain equalization scheme based on an inverse characteristic of the characteristic of a transmission line leading to the ONU. The ONU includes a CP inserting unit; a CP removing unit; and an FFT unit, an EQ unit, and an inverse FFT unit that perform equalization on the downlink CP-removed signal according to the frequency domain equalization scheme based on an inverse characteristic of the prestored characteristic of the a transmission line leading to the OLT.

Abstract: According to one example embodiment, a form factor adapter module may include a small form factor (SFF) host connector, an X2 or XENPAK edge finger connector, and a serial to XAUI transceiver. The SFF host connector may be configured receive a small form factor pluggable (SFP or SFP+) module and to transmit and receive data according to a Serial Gigabit Media Independent Interface (SGMII) or Serializer-deserializer Framer Interface (SFI) protocol. The X2 or XENPAK edge finger connector may be configured to mate with an X2 or XENPAK edge finger socket and to transmit and receive data according to a Ten Gigabit Ethernet Attachment Unit Interface (XAUI) protocol. The serial to XAUI transceiver may be coupled to both the SFF host connector and the X2 or XENPAK edge finger connector. The serial to XAUI transceiver may be configured to convert data between the SGMII or SFI protocol and the XAUI protocol.

Abstract: A system is disclosed for an improved ROSA that has increased sensitivity for permitting greater numbers of ONTs to be connected to an optical network per defined transmission line distances. The ROSA configuration includes a digital optical module with improved performance characteristics. This digital optical module has replaced a conventional photodiode with a PIN detector that is coupled with the TIA. The resulting digital optical module containing this PIN/TIA configuration when incorporated in a ROSA provides a single ROSA solution that will meet or exceed the ITU/IEEE FTTx standards for short and long distances under substantially all operating conditions.

Abstract: The present invention provides a transceiver for optical transmission in which noise can be sufficiently suppressed and a method for the same using a simple configuration. The transceiver includes an optical transmitter module in which a low frequency obtained by boosting and filtering a power-source voltage is superimposed onto and LD drive current.

Abstract: A frequency response signal transmitting device for frequency response measurement includes: a first oscillator unit configured to generate a clock signal; a clock and data recovery (CDR) unit configured to remove a jitter component of the clock signal; a pulse signal generation unit configured to receive an output signal of the CDR unit and generate a pulse signal repeated at a predetermined period; and an optical signal transmission unit configured to receive the output signal of the CDR unit and apply the received signal to an optical cable.

Abstract: A method for setting transceiver transmission parameters, in a transceiver having a plurality of components, to achieve the predetermined acceptable end-to-end bit error rate while reducing power consumption. In another aspect the invention relates to an optical transceiver system that uses digital signal processing to process the data stream sent through a fiber optical channel to compensate for transmission, reception and channel impairments to achieve the a predetermined end-to-end bit error rate and to alter its power dissipation to that sufficient to meet said end-to-end bit error rate. In one embodiment the optical transceiver system includes an optical transmitter; an optical receiver comprising an ASIC, FPGA, or other circuitry; and a controller in electrical communication with the optical receiver, wherein the controller controls power to portions of the ASIC so as to reduce power dissipation while meeting the end-to-end bit error rate.

Abstract: A topology for optical transceiver components comprises an electrical signal interface stage, a data timing and signal reformatting stage, and an optical fiber interface stage. Unlike transceiver components known in the art, functions having signals with the most jitter are partitioned into the electrical signal interface stage. Data timing functions, for example retiming or clock and data recovery, are included in the data timing and reformatting stage. Output jitter from the data timing and signal reformatting stage is approximately equal to jitter in a clock signal, enabling use of semiconductor components having jitter greater than SONET limits and thereby increasing a value of production yield. Embodiments of the invention are well suited for 40 G transmitters and receivers in nonconnectorized surface mount packages. 40 G transceivers built in accord with the invention are expected to have lower cost, smaller size, and higher production yield than 40 G transceivers known in the art.

Abstract: A passive optical network transceiver includes an avalanche photodiode, a bias voltage generator for supplying a bias voltage to the avalanche photodiode, a temperature detector for measuring the operating temperature of the avalanche photodiode, a memory for storing one reference bias voltage and a processing circuitry to process the value of the measured operating temperature and the reference bias voltage to generate a control signal for controlling the bias voltage generator to adjust the bias voltage supplied by the said bias voltage generator.

Abstract: A method and apparatus for performing an automatic power adjustment wherein a signal power level of an optical signal transmitted by an optical transceiver via an optical span to a far-end device is adjusted automatically in response to a determined span loss of the optical span to achieve a predetermined desired receive signal power level of the optical signal at the far-end device.

Abstract: An optical receiver includes a light receiving element for converting an optical signal to an electrical signal having a first bandwidth and an amplifier for amplifying the electrical signal. The amplifier has a first gain response that yields a second bandwidth that is less than the first bandwidth. The optical receiver also includes an equalizing circuit operationally coupled to the amplifier. The equalizing circuit has a second gain response that compensates for the first gain response of the amplifier so that a substantially constant net gain is imparted by the amplifier and the equalizing circuit to the electrical signal over the first bandwidth.

Abstract: A multi-channel or bidirectional optoelectronic device comprises a two or more optoelectronic components, e.g., a photodetector and a light source. A protective encapsulant can be applied to the optoelectronic device that includes hollow dielectric microspheres to reduce electrical cross-talk, and that can further include an optical absorber to reduce optical cross-talk.

Abstract: The present disclosure relates to a high-speed and/or power-saving bi-directional transceiver. The transceiver generally includes a (burst) laser driver; an output power monitoring and indicating circuit; control logic (e.g., a microcontroller unit); bi-directional optics; a photodiode bias control circuit; a limiting amplifier; and a receiver optical power monitoring circuit. Optionally, the present transceiver includes a small form factor pluggable (SFP+) connector housing. In addition, the power-saving bi-directional transceiver generally includes a transmitter (TX) energy-saving circuit, a TX burst holding circuit, a receiver (RX) energy-saving circuit, a RX continuous holding circuit and the control logic.

Abstract: A current mirror circuit and an optical receiver circuit implementing with the current mirror circuit are disclosed. The current mirror circuit provides two MOSFETs and two differential amplifiers. The MOSFETs are operated under the same bias condition even the power supply voltage decreases due to the virtual short-circuit characteristic between two inputs of the differential amplifier. One of the differential amplifiers provides a variable gain and output impedance characteristic to stabilize the feedback loop formed by this differential amplifier and one of the MOSFETs.

Abstract: One embodiment includes an integrated boot and release slide having a release slide and a boot. The release slide includes a main body, a plurality of arms, and a plurality of coupling structures. The arms extend from a first end of the main body. The coupling structures extend from a second end of the main body opposite the first end. The boot is overmolded over the coupling structures of the release slide and defines a cavity configured to slidably receive a communications cable.

Abstract: An operational optical transceiver configured to update operational firmware using an optical link of the transceiver. The optical transceiver includes at least one processor and a system memory capable of receiving firmware. The optical transceiver receives an optical signal over the optical link containing the update firmware. The optical transceiver then recovers the firmware from the optical signal. Finally, the optical transceiver provides to the system memory the recovered firmware, which when executed by the at least one processor alters the operation of the transceiver.

Abstract: A method to reduce a peak power consumption of an optical transceiver including a thermoelectric cooler (TEC) is disclosed. The transceiver includes three power units, one of which powers the temperature control unit including the TEC driver and the TEC, second one of which powers the transmitter unit including an LD and an LD driver, and the last of which powers the receiver unit. Once the transceiver is set in the host system, the transceiver first activates the first and second power units to start up the temperature control unit and the transmitter unit, and subsequently, the transceiver sets up the third power unit after the temperature of the LD is stabilized at a target temperature.

Abstract: A system for expanding PCI Express (PCIe) compliant signals over a fiber optic medium with no latency. A standardized fiber optic transceiver is adapted to provide an optimal PCIe expansion over a fiber optic medium. Signal buffers are utilized to translate and fine-tune standardized PCIe traffic to a level of low voltage differential signaling (LVDS) that is comprehensible to a wide range of fiber optic transceivers over a wide range of interface bandwidths. The intended use for such a high-speed LVDS buffer is to strengthen and enable PCIe signals over metal (copper) cable or metal printed circuit board (PCB) traces for large PCBs, such as backplanes, server motherboards, etc. By disposing the PCIe buffer used for metal (copper) cable between the PCIe bus and the fiber optic transceiver, one can achieve the signal conditioning and translating required to allow PCIe signals to pass over the fiber optic medium.

Abstract: An optical transmission/reception device includes at least one light emitting portion and at least one light receiving portion on the same substrate. The light emitting portion includes at least a lower multilayer reflector and an active layer provided on the lower multilayer reflector. A metal layer including a plurality of opening portions is provided in an upper portion of the light emitting portion. Each of the opening portions has a size smaller than a light emission wavelength of the light emitting portion.

Abstract: A new transmission link configuration with remote Er post- and pre-amplifiers where pump power is shared between a pair of fibers carrying traffic in opposite directions is proposed. A budget increase of >4 dB is demonstrated.

Abstract: A transponder having a dynamic remapping circuit remaps a value of decision threshold voltage Vdtc and a value of optical power RXP to a reference voltage Vref to minimize the bit error rate BER of a communication system. The dynamic remapping circuit implements a bilinear mapping of Vdtc and RXP to Vref with three bilinear remapping constants “a”, “b”, and “c” selected to align a remapped value of Vdtc_opt to a selected Vdtc normalization value, Vdtc_norm. A transponder in accord with an embodiment of the invention prevents BER from exceeding a threshold value of BER whether RXP or OSNR, or both, remain constant, change continuously, or change intermittently. Constants “a”, “b”, and “c” are related to parameters resulting from mathematically fitting a line to data comprising Vdtc_opt versus RXP. Another embodiment comprises a method for dynamically optimizing Vdtc and RXP to Vref in a transponder with a bilinear remapping circuit.

Abstract: The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at lower costs) by using a modulation format where spectral efficiency (a transmission bit number per a unit band width) is high, while using a low noise part of a light source.

Abstract: A circuit controlling the gain of an amplifier in an optical transmitter used for optical communication, including a detection circuit for measuring the power of the RF input to a laser; a gain controller or controlling a gain of an amplifier, and a switch connected to the gain controller, wherein the gain controller is adapted, in response to an activation of a switch, to: (i) automatically vary gain of the amplifier, and (ii) set the gain of the amplifier at a level corresponding to a reduction in the noise and/or distortion associated with the transmitter.

Abstract: An optical transceiver includes: an optical reception circuit which converts a first optical signal received from an optical cable into a first electrical data signal and outputs the first electrical data signal; an optical transmission circuit which converts a second electrical data signal into a second optical signal and outputs the second optical signal to the optical cable; a noise detection unit which detects power supply noise from a power supply voltage; and a control unit which sets at least one of operational characteristics of the optical reception circuit and operational characteristics of the optical transmission circuit in accordance with a detection result of the noise detection unit.

Abstract: The subject matter disclosed herein relates to determining a photosensor operating point.

Abstract: An optical transceiver module includes a receiving unit, a transmission driving unit, and a terminal control unit. The receiving unit outputs a receiver lost signal. The transmission driving unit includes a positive receiving signal terminal and a negative receiving signal terminal. The terminal control unit is coupled between the positive receiving signal terminal and the negative receiving signal terminal. The terminal control unit controls whether a differential terminator impedance is coupled between the positive receiving signal terminal and the negative receiving signal terminal according to the receiver lost signal.

Abstract: An optical transceiver and a method to setup the optical transceiver are disclosed, where the transceiver has a function to compensate the distortion and the dispersion due to the limited bandwidth of the electrical signal line, that of the active devices, and that of the optical fiber. The optical transceiver comprises a transmitter with an equalizer unit and a receiver also with an equalizer unit. The equalizer unit in the transmitter compensates the distortion due to the limited bandwidth of the transmission lines for the electrical signal and that of the semiconductor active device, while, the equalizer unit in the receiver compensates the dispersion due to the limited bandwidth of the optical fiber.

Abstract: An apparatus comprising an optical transceiver module. The apparatus also includes an interface coupled to the optical transceiver and comprising a plurality of pins.

Abstract: An optical transmitter apparatus for use in an optical communications network has a polarization dithering unit, an optical transmitter unit, and a transmission fiber. The polarization dithering unit is connected in series between an output of the optical transmitter unit and the transmission fiber.

Abstract: A method and an apparatus are provided for use in a parallel optical transmitter or transceiver to compensate for variations in optical crosstalk in an optical output power monitoring system that are caused by lasers being enabled and/or disabled. In particular, the method and apparatus cause adjustments to be made to the reference value of each optical channel based on determinations of whether one or more lasers of the other optical channels have been disabled or enabled. By making these adjustments, the average optical output power level of each laser of each channel can be maintained at a desired or required level even if one or more of the lasers of one or more of the other channels is enabled or disabled.

Abstract: Techniques, apparatus and systems to provide carrier signal transmission in reciprocal transmission architecture networks for optical communications.

Abstract: An optical component contains a tunable laser. The tunable laser provides an optical local oscillator signal, and the tunable laser is directly modulated to provide a modulated optical data signal. In this manner we have optimization of the channel wavelength and obtain an optimized electrical and optical bandwidth utilization. Furthermore, a method for data processing is suggested.

Abstract: An intelligent transmitter module (“ITM”) includes a CDR circuit for equalizing and retiming an electrical data signal, a driver for generating a modulation signal and/or performing waveform shaping of the equalized and retimed signal, and an optical transmitter configured to emit an optical signal representative of the data signal. A linear amplifier may also be included to amplify the modulation signal when the optical transmitter is a laser with managed chirp. Alternately or additionally, a microcontroller with a 14-bit or higher A2D can be included to control and optimize operation of the ITM. In one embodiment, the CDR, driver, linear amplifier, and/or microcontroller are flip chip bonded to a first substrate while the laser with managed chirp is bonded to a second substrate. The first substrate may comprise a multi-layer high frequency laminate.