Microsoft Technology Licensing, LLC

Applied Optoelectronics, Inc.

Other

City University of Hong Kong

Qin Li

Chao He

Wei-Ge Chen

I-Lung Ho

Chong Wang

Hsiu-Che Wang

Jack W Stokes

Dong Chen

Anton W Krantz

Kai-Sheng Lin

Michael Lewis Seltzer

Arungunram Chandrasekaran Surendran

Mu Han

Yi Liu

Wei Zhong

Vinod Prakash

Hao-Hsiang Liao

Zhengyu Miao

Ruru Chen

Elsie Marentes

Leung Tsang

The present disclosure is generally directed to utilizing capacitors stacks with capacitors mounted in a terminal-to-terminal mounting orientation to reduce overall footprint of capacitor arrays for bypass filtering circuits. In an embodiment, each capacitor stack includes at least a first capacitor, a second capacitor, and a ground plane interconnect. The first capacitor includes first and second terminals disposed opposite each other. The first terminal provides a mating surface to couple to the second capacitor, the second terminal couples to a ground plane. The second capacitor includes first and second terminals disposed opposite each other. The first terminal provides a mounting surface to electrically couple to and support the first capacitor, and the second terminal provides a mating surface to electrically and physically couple to the ground plane. Accordingly, the first capacitor can be inverted and mounted atop the second capacitor to eliminate the necessity of wire bonds, for example.

Capacitor stacks for noise filtering in high-frequency switching applications and an optical subassembly module implementing same

The present disclosure is generally directed to a lens clip that defines at least one mounting surface for coupling to and supporting an array of optical components, e.g., a laser diode and associated components, and an optical lens slot to receive and securely hold an array of optical lenses at a predetermined position relative to the optical components to ensure nominal optical coupling. The optical lens slot includes dimensions that permit insertion of each optical lens into the same and restrict travel along one or more axis. Accordingly, disposing an optical lens within the lens slot ensures correct alignment along at least two axis, e.g., Z and X, with the third axis (e.g., Y) extending parallel along the slot to permit lateral adjustment of each lens.

Lens clip for coupling and optical alignment of an optical lens array and an optical subassembly module implementing same

The present disclosure is generally directed to a lens clip that includes an optical lens slot to securely hold an optical lens at a predetermined position to mitigate effects of post-annealing shift. The lens clip includes a base that provides at least one substrate mating surface for mounting to a substrate, and at least first and second arms extending from the base. The first and second arms extend substantially parallel relative to each other and define at least a portion of an optical lens slot. The optical lens slot is configured to receive at least a portion of an optical lens and securely hold the optical lens at a predetermined position to ensure optical alignment of the optical lens, e.g., relative to an associated laser diode or other optical component, during fixation of the optical lens to the substrate using, for instance, UV-curing optical adhesives.

Lens clip for coupling and optical alignment of an optical lens and an optical subassembly module implementing same

The present disclosure is generally directed to an optical transceiver that includes a multi-channel on-board ROSA arrangement that includes an optical demultiplexer, e.g., an arrayed waveguide grating (AWG) and an array of photodiodes disposed on a same substrate. The array of photodiodes may be optically aligned with an output port of the optical demultiplexer and be configured to detect channel wavelengths and output a proportional electrical signal to an amplification circuit, e.g., a transimpedance amplifier. Each of the photodiodes can include an integrated lens configured to increase the alignment tolerance between the demultiplexer and the light sensitive region such that relatively imprecise bonding techniques, e.g., die bonding, may be utilized while still maintaining nominal optical power.

Photodiode (PD) array with integrated back-side lenses and a multi-channel transceiver module implementing same

A multi-channel transceiver, consistent with the present disclosure, includes a multiplexer/demultiplexer (MUX/DEMUX) device configured to be shared by, and support operations of, a multi-channel transmitter optical subassembly (TOSA) and multi-channel receiver optical subassembly (ROSA) within a single transceiver housing. The shared MUX/DEMUX device may be referred to herein as simply a shared AWG for ease of description and not for purposes of limitation. The shared AWG receives optical signals from a plurality of TOSA modules at different channel wavelengths via a plurality of mux input ports, and then combines the optical signals into a multiplexed optical signal, with the multiplexed optical signal being output via a mux output port. In addition, the shared AWG receives an optical signal having different channel wavelengths at a demux input port and separates channel wavelengths to be output via a plurality of demux output ports.

Optical multiplexer\demultiplexer with input and output ports on a single side, and an optical transceiver implementing same

In general, the present disclosure is directed to a thermoelectric cooler (TEC) that includes a top plate or bottom plate being formed of a high thermal conductivity material, and the other of the top plate and bottom plate being formed of a low thermal conductivity material, with the high thermal conductivity material having a thermal conductivity at least twice, and preferably five times, that of the thermal conductivity of the low thermal conductivity material. This disparity in thermal conductivity between the top plate and bottom plate materials may be referred to herein as asymmetric thermal performance.

Thermoelectric cooler (TEC) having top and bottom plates with asymmetric thermal conductivity and an optical subassembly implementing the same

A coaxial transmitter optical subassembly (TOSA) including a side-by-side laser diode and monitor photodiode package, consistent with embodiments of the present disclosure, may be used in an optical transceiver for transmitting an optical signal at a channel wavelength. In an embodiment, the coaxial TOSA includes a laser sub-mount coupled to a mounting region defined by a body of the coaxial TOSA. The laser sub-mount includes a monitor photodiode disposed adjacent to a side of a laser diode such that a sensor region of the monitor photodiode is disposed within, or in close proximity to, a light cone emitted by a light emitting surface of the laser diode. The monitor photodiode is thus configured to directly receive a portion of emitted channel wavelengths from the laser diode for monitoring purposes.

Coaxial transmitter optical subassembly (TOSA) including side-by-side laser diode and monitor photodiode arrangement

An arrayed waveguide grating (AWG) device for use in an optical transceiver is disclosed, and can de-multiplex an optical signal into N number of channel wavelengths. The AWG device can include an AWG chip, with the AWG chip providing a planar lightwave (PLC) circuit configured to de-multiplex channel wavelengths and launch the same into output waveguides. A region of the AWG chip may be tapered such that light traveling via the output waveguides encounters an angled surface of the tapered region and reflects towards an output interface region of the AWG chip. Thus detector devices may optically couple to the output interface region of the AWG chip directly, and can avoid losses introduced by other approaches which couple an output of an AWG to detectors by way of a fiber array or other intermediate device.

Techniques for direct optical coupling of photodetectors to optical demultiplexer outputs and an optical transceiver using the same

Example apparatus and methods concern performing stereo acoustic echo cancellation using a correlation based filter adaptation control approach and without using stereo de-correlation. An embodiment includes a stereo adaptive filter that produces an echo removed microphone signal from received audio signals. The embodiment includes a mono adaptive filter that produces an echo removed microphone signal from the received audio signals. A correlation detector determines a level of correlation between the received signals and provides a signal to an adaptive filter controller. The adaptive filter controller controls how the stereo adaptive filter and the mono adaptive filter adapt audio echo cancellation as a function of the correlation between the received signals. A signal selector may select for output the signal from either the stereo adaptive filter or the mono adaptive filter based, for example, on the power level of the signals.

Correlation based filter adaptation

A communications device is presented for providing bi-directional audio communications between a near-end user and a far-end user via a bidirectional communications channel. The communications device includes an adaptive echo canceller receiving a near-end audio signal and a far-end audio signal and providing an echo-canceled near-end audio signal for transmission to the far-end user via the communications channel. The adaptive echo canceller includes a first bank of analysis filters for filtering the near-end audio signal, a second bank of analysis filters for filtering the far-end audio signal, and a bank of synthesis filters for filtering sub-band echo-canceled signals generated within the adaptive echo canceller. The first and second filter banks have a frequency response optimized to reduce echo residual gain.

Filter bank optimization for acoustic echo cancellation

A voice communication end device performs quality checks to determine whether acoustic echo cancellation would be ineffective, such as due to noise or clock drift or discontinuities between incoming and outgoing voice channels. In the case where echo cancellation would prove ineffective, the device falls back on a tri-state voice switching operation that includes a bi-direction state in which both channels are on in full duplex operation, which provides a smoother transition switching between active channels. The tri-state voice switching supports both voluntary transitions where the active user voluntarily stops to yield the active channel, and forced transitions where the active user is forcedly interrupted by the other user speaking more loudly.

Voice switching for voice communication on computers

The quality and robustness of audio echo cancellation is enhanced by selectively applying glitch recovery processes based on a quality measurement of the relative offset between capture and render audio streams. For example, large and small glitch detection is enabled for low relative offset variance; large glitch detection is enabled in a medium range of relative offset variance; and neither enabled at high variance. Further, a fast glitch recovery process suspends updating the adaptive filter coefficients of the audio echo cancellation while buffers are re-aligned to recover from the glitch, so as to avoid resetting the adaptive filter. When clock drift exists between capture and render audio streams, a multi-step compensation method is applied to improve AEC output quality in case the drifting rate is low; and a resampler is used to compensate the drift in case the drifting rate is high. An anti-clipping process detects clipping of the signals, and also suspends adaptive filter updating during clipping.

Selective glitch detection, clock drift compensation, and anti-clipping in audio echo cancellation

A communication end device of a two-way communication system is shown. The device includes an audio signal capture device for capturing local audio to be transmitted to another end device, an audio signal rendering device for playing remote audio received from the other end device, and buffers for buffering the captured and rendered audio signals. The device also includes an audio echo canceller operating to predict echo from the rendered audio signal at a calculated relative offset in the captured audio signal based on an adaptive filter, and subtract the predicted echo from the signal transmitted to the other end device The calculated relative offset that is used by the audio echo canceller for a current signal sample is adjusted if a difference between it and an adjusted relative offset of a preceding sample exceeds a threshold value.

Method and apparatus for reducing timestamp noise in audio echo cancellation

An audio signal is received that might include keyboard noise and speech. The audio signal is digitized and transformed from a time domain to a frequency domain. The transformed audio is analyzed to determine whether there is likelihood that keystroke noise is present. If it is determined there is high likelihood that the audio signal contains keystroke noise, a determination is made as to whether a keyboard event occurred around the time of the likely keystroke noise. If it is determined that a keyboard event occurred around the time of the likely keystroke noise, a determination is made as to whether speech is present in the audio signal around the time of the likely keystroke noise. If no speech is present, the keystroke noise is suppressed in the audio signal. If speech is detected in the audio signal or if the keystroke noise abates, the suppression gain is removed from the audio signal.

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Houston, TX, United States of America

Qin Li