University of Illinois

Finisar Corporation

Intersymbol Communications, Inc.

Andrew Carl Singer

Naresh Shanbhag

Ryan Michael Corey

Daniel Mahgerefteh

Jonathan Ashbrook

Jacob Janovetz

Thomas Riedl

Rajamohana Hegde

Parviz Tayebati

Christopher R Cole

Yasuhiro Matsui

Xueyan Zheng

The'linh Nguyen

Ralf Koetter

Michael L Oelze

Hyeon Min Bae

Heyon Min Bae

Robert J Drost

A listening system includes one or more remote signal sources that generate one or more electronic signals, which correspond to sound in an ambient environment. A first ear microphone detects a first combination of audio signals including ambient sound and one or more propagated audio signals, corresponding to the one or more electronic signals, received at a first ear of a listener. The system includes first ear playback device and a processing device to apply a first set of audio filters including an audio filter to process a respective electronic signal of the one or more electronic signals with a first error signal, which is based on an output of the first ear microphone, to generate a first output signal to the first ear playback device, wherein acoustic cue components of the first output signal match corresponding acoustic cue components of the first combination of audio signals.

Adaptive binaural filtering for listening system using remote signal sources and on-ear microphones

A method for separating sound sources includes digitizing acoustic signals from a plurality of sources with a plurality of microphone arrays, wherein each of microphone arrays includes one or more microphones, wherein at least one of the microphone arrays may be asynchronous to another one of the microphone arrays or may be moving with respect to another one of the microphone arrays. Spatial parameters are estimated of the digitized acoustic signals. The method includes estimating time-varying source spectra for the sources from the digitized acoustic signals as a function of the digitized acoustic signals and data received from at least one other microphone array. Source signals are estimated for one or more of the sources by filtering the digitized acoustic data digitized at the respective microphone array using the spatial parameters of the digitized acoustic data and the time-varying source spectra from all or a subset of the microphone arrays.

Separating space-time signals with moving and asynchronous arrays

Aspects of the subject disclosure may include, for example, receiving, by a receiver through a medium from a transmitter, signals over an acoustic channel, where the receiving over the acoustic channel utilizes a high center frequency and provides for a high data rate, and where the medium is a fluid or a semi-solid medium. The device can receive power from the transmitter over the acoustic channel. Other embodiments are disclosed.

Method and apparatus for ultra high bandwidth acoustic communication and power transfer

Methods and apparatus for shaping and filtering quantization errors conjointly in space and time to produce a higher-precision output in a spatially and temporally oversampled array. A space-time error-shaping array system has an array of sensors, each sensor producing a temporal signal comprising quantized waveforms. A multi-input multiple-output (MIMO) discrete-time filter structure with multiple inputs, each coupled to a sensor of the array of sensors, shapes quantization errors of the array of sensors on the basis of temporal aspects of the quantized waveforms conjointly with spatial aspects of the quantized waveforms.

Space-time oversampling and error shaping for coarsely quantized arrays

A Doppler compensation system includes a transmitter unit for transmitting a signal, wherein the transmitted signal being associated with an emission time-scale, a receiving unit for receiving a signal, wherein the received signal is associated with a receive time-scale that is not equivalent to the emission time-scale, and a Doppler compensating unit configured to estimate an inverse temporal distortion function, wherein the Doppler compensating unit implements the inverse temporal distortion function to estimate the transmitted signal.

System and method for broadband doppler compensation

An adaptive Analog to Digital Converter (ADC) that adjusts the representation levels used in the conversion process so as to optimize system performance. By establishing system performance criteria by which to select or adjust the signal value range associated with each digital representation and/or the digital representation, substantially fewer bits may be used in the ADC. The systems and methods described herein enable lower-power, smaller form-factor designs as well as very high-speed operation. In particular, this technology may be beneficial for use in communications systems because it enables ADC's to operate at speeds where traditional ADC designs simply cannot.

Method and system having adjustable analog-to-digital conversion levels

An example method includes receiving a phase correction signal representing a phase difference between a source signal and a reference signal, generating a first control voltage from the phase correction signal using a charge pump circuit, generating a second control voltage from the phase correction signal in response to a digitally filtered version of the phase correction signal, wherein the second control voltage corrects for an offset error present in the first control voltage, calculating a VCO control signal based on a linear combination of the first and the second control voltages; and generating the source signal in response to the VCO control signal.

Baseband phase-locked loop

A system and method is disclosed for controlling signal conditioning parameters and a sampling parameter controlling conversion of a received signal to digital sampled values prior to decoding. The sampled values are decoded according to a comparison with expected values calculated according to a model of a transmission channel. The model is also updated from time to time by comparing the expected values with actual sampled values. Variation of the expected values over time is calculated. One or more of the signal conditioning parameters and the sampling parameter are adjusted according to a numerical minimization method such that the system BER is reduced.

Tuning system and method using a simulated bit error rate for use in an electronic dispersion compensator

A high-speed maximum likelihood sequence estimation method and device. The method includes identifying candidate paths through a state trellis based on a group of observed data, where each candidate path corresponds to a best path through a trellis beginning at one of a possible prior states (and corresponding prior data bit or bits), and then selecting one of the paths based on candidate sequence selection information, typically prior state decisions (e.g., data symbols in the form of one or more bits). The path selection, in turn, provides decoding of symbols and data bit information for use in selecting one of the candidate paths in a subsequent stage.

Method and apparatus for delayed recursion decoder

A high-speed optical transmitter comprises multiple digital lanes that are provided to a bank of digital-to-analog converters. The analog signals are then used to Phase Shift Keyed (PSK) modulation using a Chirp Managed Laser (CML)-based transmitter, and potentially using dual polarization. A corresponding optical receiver receives the sequence of optical signals at a demodulator. For each polarization, the demodulator includes a corresponding demodulation channel that is configured to demodulate that polarization component of the optical signal into one or more signal components. Each of these signal components is converted into a corresponding digital signal using a corresponding analog-to-digital converter. In the case of higher-order PSK modulation (e.g., 8PSK or higher), for each polarization, the analog converter has a lower sampling rate than for QPSK modulation.

Phase shift keyed modulation of optical signal using chirp managed laser

A method for generating D-N-PSK optical signals is disclosed wherein a laser is modulated to generate optical signal pairs including phase modulated and fixed phase portions, the phase modulated portions having a frequency encoding one or more data symbols and the fixed phase portion having a carrier frequency and a phase corresponding to the immediately preceding phase modulated portion. The output of the laser is passed through an optical spectrum reshaper having a transmission function chosen to attenuate a plurality of the phase modulated portions relative to the fixed phase portions. The phase modulated portions may have N frequency levels located on either side of the carrier frequency. One of the N frequency levels may be equal to the carrier frequency.

Chirped laser with passive filter element for differential phase shift keying generation

Methods and systems are provided for an improved phase detector utilizing analog-to-digital converter (ADC) components. In an embodiment, the method includes from an ADC having a sampling clock signal that determines sampling instants, obtaining a first comparison value between an analog signal and a first threshold voltage at a first sampling instant, and obtaining a second comparison value between the analog signal and a second threshold voltage at a second sampling instant. The method further includes, from a supplemental circuit, obtaining a third comparison value between the analog signal and a third threshold voltage at a third sampling instant between the first and second sampling instants. The method further includes processing the first, second, and third comparison values to determine a phase relationship between the analog signal and the sampling clock.

Phase detector utilizing analog-to-digital converter components

A method and device employing an iterative MMSE equalization-decoder soft information exchange decoding. The method uses a MMSE equalizer which receives and outputs soft information. The equalizer exchanges soft information with a soft input soft output decoder, preferably an error correction decoder. The nature of the equalizer permits solutions beyond one-dimensional data streams and permits solutions for long channel lengths and multi-dimensional data since the solution is not a function of the channel impulse response.

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Mahomet, IL, United States of America

Andrew Carl Singer