Abstract: The invention relates to a system and method of communication between optical transceivers in an optical WDM network, wherein a broad-band modulation of optical signals in a primary frequency band is utilized for transmitting primary high-speed data, while a plurality of relatively low-frequency in-band subcarriers is used to modulate the optical signals to transmit secondary data between network nodes, wherein the plurality of low-frequency subcarriers lie at least in part within the primary frequency band.

Abstract: An optical transceiver that includes a modification that prevents interoperability with standard transceivers, while enabling them to work in the same slots and equipment as standard transceivers, provided that they are interoperating with a similarly modified transceiver on the other end of the optical link. Ideally, the polarity of the data in both the transmit and receive direction is inverted resulting in valid data for a link when a pair of modified modules are used and invalid data when a modified module is used with a standard fiber optic transceiver. The function is otherwise transparent to the host equipment.

Abstract: An optical transceiver that includes a modification that prevents interoperability with standard transceivers, while enabling them to work in the same slots and equipment as standard transceivers, provided that they are interoperating with a similarly modified transceiver on the other end of the optical link. Ideally, the polarity of the data in both the transmit and receive direction is inverted resulting in valid data for a link when a pair of modified modules are used and invalid data when a modified module is used with a standard fiber optic transceiver. The function is otherwise transparent to the host equipment.

Abstract: This disclosure concerns optoelectronic transceivers. In one example, a transceiver is implemented as an uncompensated architecture that is substantially compliant with the SFP MSA and is capable of effective operation at a data rate of about 8.5 Gb/s. The transceiver includes a TOSA, ROSA, a printed circuit board, an LDPA disposed on the printed circuit board and configured for communication with the TOSA and the ROSA. Finally, the transceiver includes SFP compliant optical and electrical connections.

Abstract: This disclosure concerns transceivers that include CDR bypass functionality. In one example, a 10 G XFP transceiver module includes integrated CDR functionality for reducing jitter. The 10 G XFP transceiver module also implements CDR bypass functionality so that the CDR can be bypassed at rate less than about 10 Gb/s, such as the Fibre Channel 8.5 Gb/s rate for example.

Abstract: Out-of-band data communication of diagnostic or other data is performed using transceivers in a data or communication network. A light beam or other carrier is modulated with high-speed data and out-of-band data to create a double modulated data signal. A physical layer signal is created that includes modulations of the double modulated signal. The physical layer signal is transmitted onto a physical link. The diagnostic or other data can be transmitted in the out-of-band signal without substantially reducing or otherwise interfering with the transmission rate of the high-speed data.

Abstract: A tunable laser source with integrated optical modulator. The tunable laser source is a widely tunable semiconductor laser that is comprised of an active region on top of a thick, low bandgap, waveguide layer, wherein both the waveguide layer and the active region are fabricated between a p-doped region and an n-doped region. An electro-absorption modulator is integrated into the semiconductor laser, wherein the electro-absorption modulator shares the waveguide layer with the semiconductor laser.

Abstract: A tunable laser source (10) with an integrated optical modulator (20). The laser source (10) is a widely tunable semiconductor laser that is comprised of an active region on top of a thick low bandgap, waveguide layer (22), wherein both the waveguide layer (220) and the active region are fabricated between a p-doped region and an n-doped region. An electro-absorption modulator (20) is integrated into the semiconductor laser (10), wherein the electro-absorption modulator (20) shares the waveguide layer (22) with the semiconductor laser.

Abstract: A semiconductor tunable laser (10) and an interferometer (12) coupled to the tunable laser (10) are monolithically fabricated in a semiconductor heterostructure. The laser also comprises a buried ridge stripe waveguide laser. The interferometer (12) has a semiconductor optical amplifier (38) coupled in each arm. A cross-gain semiconductor optical amplifier converter is coupled to the interferometer (12). The semiconductor optical amplifier (38) coupled in each arm is biased so that an optical path length difference between the two arms is in antiphase which results in destructive interference. The output of the tunable laser (10) is coupled to a coupler. A semiconductor optical amplifier (38) is used as a gain controller for the semiconductor optical amplifiers in the interferometer (12) to allow wavelength conversion over a larger range of input signal powers.

Abstract: Systems and methods for biasing an externally modulated laser. An inductorless bias T network is provided that includes a terminating resistor in series with a capacitor. The capacitor is an open circuit for a bias signal and a virtual ground for an RF signal. Thus, the RF signal is terminated by the terminating resistor without dissipating the bias signal through a ground return path of the RF signal. Using a charge pump inverter, a positive supply can be used to positively bias a laser and negatively bias the external modulator through the terminating resistor. A negative power supply is not required. A swing voltage provided by the RF signal causes the external modulator to modulate the light emitted by the laser.

Abstract: A small form factor transceiver module that incorporates an externally modulated laser (EML). The transceiver module has a transmitter optical subassembly with a header assembly having a base with a platform extending through. The platform has a plurality of conductive traces extending through the platform for making connections on both sides of the base. A thermoelectric cooler (TEC) is used to dissipate heat from a laser within the header assembly. The TEC dissipates heat sufficiently to allow the EML to be used in the header assembly. In this manner, EMLs can be used in relatively small optical devices, including small form factor transceivers that comply with the XFP standard. The XFP modules with EMLs can be used for longer links than XFPs without EMLs. In addition, EMLs can be stabilized using TECs so that XFP modules can be used for DWDM-type applications.

Abstract: This disclosure is concerned with transceiver modules. In one example, a transceiver module includes a receiver optical subassembly, as well as a transmitter optical subassembly having a header assembly and an externally modulated laser (EML). The header assembly includes a base with first and second sides, as well as a platform attached to the base and having an inside portion near the first side of the base and an outside portion near the second side of the base. The platform of the header assembly further includes a conductive pathway extending through part of the platform. The EML is supported by the platform and electrically communicates with the conductive pathway of the platform. The EML can be passively or actively cooled.

Abstract: An optical modulator includes first and second modulator segments. The first and second modulator segments form an optical signal path for an optical signal. The optical modulator also includes an electrical signal path capable of receiving and carrying a modulation signal, which is applied to the optical signal at the first and second modulation segments to generate a modulated optical signal. An inductive element may be disposed between electrical inputs to the first and second modulator segments. The optical modulator may be an electro-absorption modulator (EAM). The inductive element may be an inductor or a transmission line segment.

Abstract: Out-of-band data communication of diagnostic or other data is performed using transceivers in a data or communication network. A light beam or other carrier is modulated with high-speed data and out-of-band data to create a double modulated data signal. A physical layer signal is created that includes modulations of the double modulated signal. The physical layer signal is transmitted onto a physical link. The diagnostic or other data can be transmitted in the out-of-band signal without substantially reducing or otherwise interfering with the transmission rate of the high-speed data.

Abstract: A small form factor transceiver module that incorporates an externally modulated laser (EML). The transceiver module has a transmitter optical subassembly with a header assembly having a base with a platform extending through. The platform has a plurality of conductive traces extending through the platform for making connections on both sides of the base. A thermoelectric cooler (TEC) is used to dissipate heat from a laser within the header assembly. The TEC dissipates heat sufficiently to allow the EML to be used in the header assembly. In this manner, EMLs can be used in relatively small optical devices, including small form factor transceivers that comply with the XFP standard. The XFP modules with EMLs can be used for longer links than XFPs without EMLs. In addition, EMLs can be stabilized using TECs so that XFP modules can be used for DWDM-type applications.

Abstract: An electroabsorption modulator comprises a tandem arrangement of a conventional electroabsorption (EA) modulator element and a phase modulator element. The EA modulator element is driven by the digital data signal and the phase modulator is driven by a chirp tuning control signal, such as the complement of the data signal. By controlling the amplitude and/or bias of the chirp tuning control signal, the frequency chirp of the intensity-modulated output signal from the EA modulator element can be controlled.

Abstract: A small form factor transceiver module that incorporates an externally modulated laser (EML). The transceiver module has a transmitter optical subassembly with a header assembly having a base with a platform extending through. The platform has a plurality of conductive traces extending through the platform for making connections on both sides of the base. A thermoelectric cooler (TEC) is used to dissipate heat from a laser within the header assembly. The TEC dissipates heat sufficiently to allow the EML to be used in the header assembly. In this manner, EMLs can be used in relatively small optical devices, including small form factor transceivers that comply with the XFP standard. The XFP modules with EMLs can be used for longer links than XFPs without EMLs. In addition, EMLs can be stabilized using TECs so that XFP modules can be used for DWDM-type applications.

Abstract: A small form factor transceiver module that incorporates an externally modulated laser (EML). The transceiver module has a transmitter optical subassembly with a header assembly having a base with a platform extending through. The platform has a plurality of conductive traces extending through the platform for making connections on both sides of the base. A thermoelectric cooler (TEC) is used to dissipate heat from a laser within the header assembly. The TEC dissipates heat sufficiently to allow the EML to be used in the header assembly. In this manner, EMLs can be used in relatively small optical devices, including small form factor transceivers that comply with the XFP standard. The XFP modules with EMLs can be used for longer links than XFPs without EMLs. In addition, EMLs can be stabilized using TECs so that XFP modules can be used for DWDM-type applications.

Abstract: A wavelength monitor is provided based on the transmission response of an optical filter. The monitor provides feedback to the laser enabling it to lock to any given wavelength within its tuning range. The invention is also a process for integrating the wavelength monitor directly on chip with a variety of tunable semiconductor lasers. The invention also comprises a method for controlling the wavelength of a tunable laser by using a wavelength monitor to measure the output light and provide feedback to a control system. The laser and wavelength monitor are integrated together on a single indium phosphide chip. The wavelength monitor comprises a filter with a wavelength dependent transmission function and a pair of detectors. One detector is illuminated with light that has passed through the filter and the other provides a reference to measure the input intensity. Taking the ratio of the filtered light level to the unfiltered light provides a wavelength dependent wavelength.

Abstract: An electroabsorption modulator comprises a tandem arrangement of a conventional electroabsorption (EA) modulator element and a phase modulator element. The EA modulator element is driven by the digital data signal and the phase modulator is driven by a chirp tuning control signal, such as the complement of the data signal. By controlling the amplitude and/or bias of the chirp tuning control signal, the frequency chirp of the intensity-modulated output signal from the EA modulator element can be controlled.