Abstract: The temperature at different locations along a multiplexed laser array may be monitored by sensing temperature at two locations within a transmitter optical subassembly (TOSA) package housing the laser array. The temperature at the two locations is used to determine a temperature tilt across the laser array. Estimated temperatures may then be determined at one or more other locations along the laser array from the temperature tilt. The estimated temperature(s) may then be used to adjust the temperature proximate the other locations, for example, for purposes of tuning lasers at those locations along the laser array to emit a desired channel wavelength. The TOSA package may be used in an optical transceiver in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON).

Abstract: A tunable laser with multiple in-line sections generally includes a semiconductor laser body with a plurality of in-line laser sections each configured to be driven independently to generate laser light at a wavelength within a different respective wavelength range. The wavelength of the light generated in each of the laser sections may be tuned, in response to a temperature change, to a channel wavelength within the respective wavelength range. A switch module may be configured to couple a signal from a laser driver to a selected one of the plurality of in-line laser sections, wherein the signal modulates the laser light generated by the in-line laser section. The selected in-line section may be DC biased to a lasing state and the non-selected in-line sections may be DC biased to a non-lasing or transparent state.

Abstract: The drive current of the switch in a switching power converter is adjusted dynamically according to line or load conditions within a switching cycle and/or over a plurality of switching cycles. The magnitude of the switch drive current can be dynamically adjusted within a switching cycle and/or over a plurality of switching cycles, in addition to the pulse widths or pulse frequencies of the switch drive current.

Abstract: A method for securing a rigid or semi-rigid article to a textile is described. The method can include the steps of positioning the article in a mold cavity of a mold; laying the textile between opposed mold portions for forming the mold cavity with a textile region of the textile extending across the mold cavity; closing the mold to clamp the textile between the opposed mold portions and substantially seal the article and the textile region in the mold cavity; filling the mold cavity with moldable material; and curing the moldable material to form an enclosure undetachably molded over the article and the textile region and embedding the article.

Abstract: A laser array mux assembly generally includes an array of laser emitters coupled to an optical multiplexer, such as an arrayed waveguide grating (AWG), with an external partial reflector after the multiplexer. Each of the laser emitters may include a gain region that emits light across a range of wavelengths including, for example, channel wavelengths in an optical communication system. The AWG filters the emitted light from each of the laser emitters at different channel wavelengths associated with each of the laser emitters. The reflector reflects at least a portion of the filtered light such that lasing occurs at the channel wavelengths of the reflected light. The laser array mux assembly may be used to generate an optical signal at a selected channel wavelength or to generate and combine optical signals at multiple channel wavelengths.

Abstract: A multi-channel optical transceiver includes a transmitter optical subassembly (TOSA) with a thermal arrayed waveguide grating (AWG) for multiplexing optical signals and a receiver optical subassembly (ROSA) with an athermal AWG for demultiplexing optical signals. The TOSA may also include a laser array optically coupled to the thermal AWG and a temperature control system thermally coupled to the laser array and the thermal AWG to control temperature for wavelength tuning. The temperature control system in the TOSA may include a thermoelectric cooler (TEC) that cools both the laser array and the thermal AWG. Because the athermal AWG in the ROSA is temperature independent, the ROSA does not include a TEC, thereby reducing power consumption and conserving space. The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON).

Abstract: An extended cavity Fabry-Perot laser assembly provides relatively narrow mode spacing while allowing relatively high speed optical modulation. The extended cavity Fabry-Perot laser assembly generally includes an exit reflector physically separated from a laser emitter (e.g., a gain chip) to extend the lasing cavity and narrow the mode spacing while maintaining a relatively small gain region in the laser emitter capable of higher speed optical modulation. The extended cavity Fabry-Perot laser assembly may be used in a multi-channel transmitter in a wavelength division multiplexed (WDM) optical system that selects a channel wavelength for the transmitter from among multiple channel wavelengths emitted by the laser assembly. The narrow mode spacing may be less than a WDM channel width, and more specifically, may be less than a channel passband of an arrayed waveguide grating (AWG) or other filter used to select the channel wavelength.

Abstract: A system is provided for improved coupling of photodetectors to optical demultiplexer outputs, for example an arrayed waveguide grating (AWG), using a refractive index matched material. In one embodiment, the system may include an optical demultiplexer including multiple optical outputs corresponding to multiple signal channels and a photodetector array including a plurality of photodiodes aligned with the multiple optical outputs. The system may also include an epoxy disposed within a gap between each of the photodiodes and each of the corresponding optical outputs of the optical demultiplexer. The epoxy may be configured to provide an index of refraction that is matched to the optical demultiplexer.

Abstract: Individual channels of a multiplexed laser array in a multi-channel optical transmitter are monitored at an output of an optical multiplexer. The monitoring may be used to confirm proper operation of each of the channels in the multiplexed laser array and/or to perform wavelength locking on each of the channels. Monitoring at the output of the optical multiplexer avoids the use of multiple photodetectors coupled directly to multiple lasers in the multiplexed laser array. The multiplexed laser array generally includes a plurality of laser emitters optically coupled to an optical multiplexer such as an arrayed waveguide grating (AWG). An optical transmitter with a monitored multiplexed laser array may be used, for example, in an optical line terminal (OLT) in a wavelength division multiplexed (WDM) passive optical network (PON) or in any other type of WDM optical communication system capable of transmitting optical signals on multiple channel wavelengths.

Abstract: A parallel cavity tunable laser generally includes a semiconductor laser body defining a plurality of parallel laser cavities with a common output. Each of the parallel laser cavities is configured to be driven independently to generate laser light at a wavelength within a different respective wavelength range. The wavelength of the light generated in each of the laser cavities may be tuned, in response to a temperature change, to a channel wavelength within the respective wavelength range. The laser light generated in each selected one of the laser cavities is emitted from the common output at a front facet of the laser body. By selectively generating light in one or more of the laser cavities, one or more channel wavelengths may be selected for lasing and transmission.

Abstract: A computer implemented method manages display application forms, and receives instructions to display an application on the computer with multiple input fields. Whether each input field is mandatory or optional is determined. Input fields are sorted based whether they are mandatory or optional, and handlers which correspond to the input fields, are displayed based on a variety of display factors.

Abstract: Selective processing of one or more packets to be transmitted from a wireless communication device to another wireless communication device is effective to reduce the peak to average power ratio (PAPR) of the transmission. The one or more packets are transmitted via two or more sub-bands of an available transmission medium. The number of coefficients or factors within that sequence corresponds to the number of sub-bands via which the one or more packets are to be transmitted. Also, a phase ramp or time-domain cyclic shift may be added to one or more of the packets after having undergone multiplication by one of the coefficients or factors within the sequence.

Abstract: In some aspects, the disclosure is directed to methods and systems for transmitting to static and non-static devices. An access point having a plurality of antennas can send a plurality of sounding frames from the plurality of antennas to a plurality of devices. The access point can identify, based on responses to the plurality of sounding frames, at least one static device from the plurality of devices. The access point can assign, based on the responses to the plurality of sounding frames, to each of the at least one static device, a corresponding one of the plurality of antennas for operation in a directional mode for transmissions to the corresponding static device, and the remaining antennas from the plurality of antennas for operation in an omnidirectional mode.

Abstract: A bidirectional optical subassembly (BOSA) optical networking unit (ONU) generally includes a BOSA housing. A tunable laser is located in the BOSA housing and is configured to generate a first optical signal for transmission at a first selected wavelength based on temperature control. The tunable laser is a distributed feedback (DFB) laser diode. A thermal management device is also located in the BOSA housing and is configured to provide the temperature control. A photo diode is further located in the BOSA housing and is configured to receive a second optical signal at a second selected wavelength. The BOSA housing comprises an alloy of stainless steel or an alloy of Kovar.

Abstract: A method for improving multiple-user (MU) multiple-input-multiple-output (MIMO) protocol efficiency includes transmitting an MU frame to multiple devices. The MU frame is beamformed to enable a corresponding one of the devices to receive an intended stream at high power. The MU frame includes an additional sounding-field. Acknowledgement (ACK) responses are received from at least some of the plurality of devices. Each of the ACK responses includes a sounding response frame including a channel feedback.

Abstract: Short training field (STF) for use within single user, multiple user, multiple access, and/or MIMO wireless communications. An STF design as is made such that the power associated with the tone indices at the edges of the STF design is relatively less than the power associated with the tone indices more centrally located within the STF design. Also, when multiple respective operational modes are supported (e.g., 1 MHz and 2 MHz), the respective STF designs corresponding to those respective operational modes have a great deal of similarity. For example, the respective STF designs for different respective operational modes may have certain common STF tone indices among those respective STF designs.

Abstract: In some aspects, the disclosure is directed to methods and systems for transmitting packets (including but not limited to MU-MIMO packets). An access point communicating wirelessly with a plurality of devices can determine that a first packet for a first device of the plurality of devices has a first transmission duration. The access point can determine that a second packet for a second device of the plurality of devices has a second transmission duration shorter than the first transmission duration. The access point can adjust, based on the determination, a transmission power or a modulation and coding scheme to transmit the second packet during a third transmission duration. The third transmission duration can be greater than the second transmission duration.

Abstract: A two-section semiconductor laser includes a gain section and a modulation-independent grating section to reduce chirp. The modulation-independent grating section includes a diffraction grating for reflecting light and forms a laser cavity with the gain section for lasing at a wavelength or range of wavelengths reflected by the diffraction grating. The gain section of the semiconductor laser includes a gain electrode for driving the gain section with at least a modulated RF signal and the grating section includes a grating electrode for driving the grating section with a DC bias current independent of the modulation of the gain section. The semiconductor laser may thus be directly modulated with the modulated RF signal without the modulation significantly affecting the index of refraction in the diffraction grating, thereby reducing chirp.

Abstract: Phase rotation for preambles within multiple user, multiple access, and/or MIMO wireless communications. An appropriately designed phase rotation vector and/or appropriately designed cyclic shift delays (CSDs) are applied to respective sub-band components of the preamble. With appropriately designed CSDs, certain fields within the preamble are not modified. For example, a legacy short training field (L-STF) of the preamble is not changed when using appropriately designed CSDs. The respective CSDs may be implemented as integer multiples of a common CSD (e.g., 0×CSD, 1×CSD, 2×CSD, etc. such that one of the values of such a CSD vector may be zero [0], another may be the common CSD itself, etc.). Also, by employing an appropriately designed phase rotation vector and integer multiples of a CSD to a preamble, the respective peak to average power ratio (PAPR) between different respective fields within the preamble may be minimized.

Abstract: A device includes an array of optical transmitters having first and second temperature sensors each disposed at or near a first and second end of the array of the transmitters. The device includes a controller in communication with the temperature sensors and the transmitters. The controller receives temperature measurements from the temperatures sensors and determines a temperature difference between a first temperature measurement of the first temperature sensor and a second temperature measurement of the second temperature sensor. The controller determines a compensation for each transmitter within the transmitter array based on the temperature difference and a transmitter position within the array of transmitters. The compensation causes the corresponding transmitter to transmit at a wavelength associated with that transmitter. The controller executes the compensations for the transmitters.