Abstract: Noise introduced into touch sensor panel measurements, for example, from display data lines of a display device proximate to the touch sensor panel, can be reduced. In some examples, touch sensing operations and display operations can be synchronized. For example, touch sensing scans (or scan steps) can begin with the rising edge of a display line synchronization signal. Additionally, the display noise can be characterized for the system. Display noise characterization and timing synchronization can be used to discard touch sensing samples including display noise injected into the touch sensor panel that may be synchronized to the display data line synchronization signal. In some examples, a window can be generated based on the characterized display noise, and the window can be applied to annihilate display noise. The application of the window can be time-dependent to account for offsets between the occurrence of the display noise and the touch sensing operation.

Abstract: Errors in touch signals due to grip and finger coupling to routing traces can be compensated. In some examples, reference traces can be provided to measure a signal contribution from a user's grip to routing traces. In some examples, shielding electrodes can be provided to reduce fringing field coupling between a user's grip and routing traces that are missing a neighboring trace. In some examples, a global correction for finger to trace coupling can be performed based on stored matrices that characterize cross-coupling between touch sensor electrodes in a touch sensor electrode array. In some examples, a determined touch location can be used to apply localized matrix correction to a subset of touch sensor electrodes in the touch sensor electrode array. In some examples, correction for multiple touch locations can be corrected in a specified order to avoid compensating for crosstalk effects of a single touch sensor electrode multiple times.

Abstract: Improved sensing can include modified sampling and/or processing to improve performance against noise due to environmental variations and interference. In some examples, improved interference rejection can be achieved by sampling a sensor multiple times during settled periods. In some examples, the excitation signal and sampling window can be dynamically adjusted to satisfy drift and/or interference specifications based on various operating conditions or the operating environment. In some examples, drift performance can be traded off to improve interference performance. In some examples, improved immunity to environmental variations can be achieved by equalizing sensor outputs in accordance with characterization of the sensing system. In some examples, improved performance can be achieved by sampling the sensor continuously and using an optimized window function to improve performance against noise.

Abstract: Improved sensing can include modified sampling and/or processing to improve performance against noise due to environmental variations and interference. In some examples, improved interference rejection can be achieved by sampling a sensor multiple times during settled periods. In some examples, the excitation signal and sampling window can be dynamically adjusted to satisfy drift and/or interference specifications based on various operating conditions or the operating environment. In some examples, drift performance can be traded off to improve interference performance. In some examples, improved immunity to environmental variations can be achieved by equalizing sensor outputs in accordance with characterization of the sensing system. In some examples, improved performance can be achieved by sampling the sensor continuously and using an optimized window function to improve performance against noise.

Abstract: Errors in touch signals due to grip and finger coupling to routing traces can be compensated. In some examples, reference traces can be provided to measure a signal contribution from a user's grip to routing traces. In some examples, shielding electrodes can be provided to reduce fringing field coupling between a user's grip and routing traces that are missing a neighboring trace. In some examples, a global correction for finger to trace coupling can be performed based on stored matrices that characterize cross-coupling between touch sensor electrodes in a touch sensor electrode array. In some examples, a determined touch location can be used to apply localized matrix correction to a subset of touch sensor electrodes in the touch sensor electrode array. In some examples, correction for multiple touch locations can be corrected in a specified order to avoid compensating for crosstalk effects of a single touch sensor electrode multiple times.

Abstract: Position-based sensing methods and systems can be used to transmit data from an input device to a touch-sensitive device. For example, the touch sensing system may perform one or more coarse input device sub-scans to determine a coarse location of the input device. The coarse location can be used to select one or more touch sensors (or sensor channels) to sample for decoding data encoded in the stimulation signals from the input device. During one or more fine input device sub-scans, the touch sensing system can determine a fine location of the input device and decode the data from the input device sampled from the selected touch sensors (or sensor channels).

Abstract: A touch sensing system can demodulate sensor data using a dynamically adjusted demodulation waveform and/or demodulation window. The demodulation waveform and/or demodulation window can be dynamically adjusted to account for dynamically changing noise in a touch sensing system. The system can dynamically adjust the demodulation window based on noise measured by the touch sensing system to generate an optimized or otherwise noise-tailored window to suppress detected noise. In some examples, the noise measured by the touch sensing system can be sampled from sense channels localized to a detected touch.

Abstract: Position-based sensing methods and systems can be used to transmit data from an input device to a touch-sensitive device. For example, the touch sensing system may perform one or more coarse input device sub-scans to determine a coarse location of the input device. The coarse location can be used to select one or more touch sensors (or sensor channels) to sample for decoding data encoded in the stimulation signals from the input device. During one or more fine input device sub-scans, the touch sensing system can determine a fine location of the input device and decode the data from the input device sampled from the selected touch sensors (or sensor channels).

Abstract: Various embodiments provide systems and methods for performing clock recovery on a received signal using a split loop architecture. A split loop timing recovery apparatus is provided comprising a first path configured for performing frequency offset tracking on a signal by adjusting a receiver clock frequency to match a remote transmitter frequency associated with the signal and a second path configured for tracking random jitter on the signal.

Abstract: Various embodiments provide systems and methods for performing clock recovery on a received signal using a split loop architecture. A split loop timing recovery apparatus is provided comprising a first path configured for performing frequency offset tracking on a signal by adjusting a receiver clock frequency to match a remote transmitter frequency associated with the signal and a second path configured for tracking random jitter on the signal.

Abstract: Techniques for calibrating interleaved analog-to-digital converter (ADC) arrays are presented. A transceiver comprises an ADC component comprising an array of interleaved sub-ADCs, and an auxiliary path associated with an auxiliary sub-ADC used to facilitate calibrating a sampling array by comparing the auxiliary path signal to signals of the sub-ADCs in the array. A calibration component employs a phase-interpolator and analog delay lines to adjust the auxiliary sub-ADC to enable the auxiliary sub-ADC to be lined up to any one of the sampling instants of the sampling array. The calibration component compares the auxiliary signal to sub-ADC signals, determines path differences between the sub-ADC paths based on the comparison results, and calibrates the sub-ADCs and sub-ADC paths to reduce the path differences to mitigate distortion in a digital stream produced from combining the digital substreams produced by the sub-ADCs in the array.

Abstract: Various embodiments provide systems and methods for performing clock recovery on a received signal using a split loop architecture. A split loop timing recovery apparatus is provided comprising a first path configured for performing frequency offset tracking on a signal by adjusting a receiver clock frequency to match a remote transmitter frequency associated with the signal and a second path configured for tracking random jitter on the signal.

Abstract: Embodiments of methods and apparatus for reducing electromagnetic interference of a received signal are disclosed. One method includes receiving a signal over at least two conductors, extracting a common-mode signal from the at least two conductors, processing the common-mode signal, and reducing electromagnetic interference of the received signal by summing the processed common-mode signal with the received signal.

Abstract: In a first embodiment of the present invention, a clock recovery system is provided comprising: a phase comparator; an integrator coupled to the phase comparator; a numerically controlled oscillator coupled to the integrator; and a mixer coupled to the numerically controlled oscillator and to the phase comparator.

Abstract: Techniques for calibration of high-speed interleaved analog-to-digital converter (ADC) arrays are presented. A transceiver comprises an ADC component that comprises an array of sub-ADCs that can be interleaved to facilitate high-speed data communications. The ADC component processes signals received from a remote transmitter to facilitate recovering the received data. The transceiver can comprise a calibration component that determines transfer characteristics of the communication channel or medium between the transceiver and the remote transmitter, and the transfer characteristics of the remote transmitter to each of the sub-ADCs of the array, based on the recovered data.

Abstract: Techniques for fast filtering for a transceiver are presented. A multidimensional filter processor component (MDFPC) can perform configurations and adaptations of multiple digital filters of a transceiver. The MDFPC can treat multiple, separate filters of a transceiver as a single larger multidimensional filter, and jointly update the multiple filters in a single adaptation operation instead of performing multiple adaptation operations on multiple filters. To facilitate multidimensional filter adaptation, the MDFPC can manage respective cross-correlations associated with the inputs of the filters. The MDFPC can facilitate multidimensional filter adaptation by performing multidimensional filter adaptation in the frequency domain, wherein the adaptation can be performed in parallel for multiple frequency sub-channels.

Abstract: Techniques for fast filtering for a transceiver are presented. A multidimensional filter processor component (MDFPC) can perform configurations and adaptations of multiple digital filters of a transceiver. The MDFPC can treat multiple, separate filters of a transceiver as a single larger multidimensional filter, and jointly update the multiple filters in a single adaptation operation instead of performing multiple adaptation operations on multiple filters. To facilitate multidimensional filter adaptation, the MDFPC can manage respective cross-correlations associated with the inputs of the filters. The MDFPC can facilitate multidimensional filter adaptation by performing multidimensional filter adaptation in the frequency domain, wherein the adaptation can be performed in parallel for multiple frequency sub-channels.

Abstract: Embodiments of methods, apparatuses, and systems for signal processing of multiple input signals to control peak amplitudes of a combined signal are disclosed. One method includes receiving a plurality of input signals, generating a combined signal, the combined signal comprising a plurality of sub-channels, wherein each sub-channel includes a representation of at least a portion of at least one of the plurality of input signals, and processing the representation of the least a portion of the at least one of the plurality of input signals of at least one of the sub-channels, to reduce a peak-to-average-power ratio (PAR) of the combined signal.

Abstract: Embodiments of methods, apparatuses and systems for transceiver processing are disclosed. One method includes a transceiver receiving a data stream from a link partner transceiver. A link parameter of a link between the transceiver and the link partner transceiver is determined. Allocation of transceiver processing between high-latency processing and low-latency processing is based at least in part on the link parameter.

Abstract: Embodiments of methods, apparatuses, and systems for preprocessing a transmit signal of a transceiver are disclosed. One method includes estimating parameters of a communication link between the transceiver and a link partner transceiver, estimating cross-talk coupling of the transceiver to at least one other transceiver, and adjusting at least one of a transmit power or a transmit signal waveform based on the estimated parameters and estimated cross-talk. One apparatus includes a transceiver that is operative to obtain parameters of a communication link between the transceiver and a link partner transceiver, and to obtain a representation of cross-talk coupling of the transceiver to at least one other transceiver. Further, a controller of the transceiver is operative to adjust at least one of a transmit power level or a transmit signal waveform based on the estimated parameters and estimated cross-talk.