Patent classifications
H04L25/03267
Methods and systems for providing multi-stage distributed decision feedback equalization
Pre-charging two or more sets of nodes to set a differential output of a multi-input summation latch connected to the two or more sets of nodes in a pre-charged state, the two or more sets of nodes comprising a set of data signal nodes and a set of DFE correction nodes, in response to a sampling clock, generating a differential data voltage and an aggregate differential DFE correction signal, and generating a data decision by driving the differential output of the multi-input summation latch into one of two possible output states according to a summation of the differential data voltage signal and the aggregate differential DFE correction signal and subsequently holding the data decision by holding the differential output of the multi-input summation latch in a latched state for a duration determined by the sampling clock.
MULTIPHASE DATA RECEIVER WITH DISTRIBUTED DFE
Methods and systems are described for receiving an input data voltage signal at a first data decision circuit of set of pipelined data decision circuits, receiving an aggregate decision feedback equalization (DFE) correction current signal from a first analog current summation bus, the aggregate DFE correction current signal comprising a plurality of DFE tap-weighted currents from respective other data decision circuits of the set of pipelined data decision circuits, determining a data output decision value based on the received input data voltage signal and the received aggregate DFE correction current signal, and generating at least one outbound DFE tap-weighted current on at least one other analog current summation bus connected to at least one other data decision circuit of the set of pipelined data decision circuits.
APPARATUSES AND METHODS FOR PULSE RESPONSE SMEARING OF TRANSMITTED SIGNALS
Embodiments of the disclosure include signal processing methods to reduce crosstalk between signal lines of a channel bus using feed forward equalizers (FFEs) configured smear pulse response energy transmitted on signal lines of the channel to reduce pulse edge rates. The coefficients for the FFE may be based on crosstalk interference characteristics. Smearing or spreading pulse response energy across a longer time period using a FFE increases inter-symbol interference (ISI). To counter increased inter-symbol interference caused by smearing pulse response energy, receivers configured to recover symbol data transmitted on the channel bus may each include respective decision-feedback equalizers (DFEs) that are configured to filter ISI from transmitted symbols based on previous symbol decisions of the channel. The combination of the FFE configured to smear pulse responses and the DFE to filter ISI may improve data eye quality for recovery of transmitted data on a channel bus when crosstalk dominates noise.
Methods and apparatus for a continuous time linear equalizer
Various embodiments of the present technology comprise a method and apparatus for a continuous time linear equalizer (CTLE). In various embodiments, the CTLE comprises a cross-coupled transistor pair that operates as a negative impedance converter. The CTLE produces a transfer function that provides high gain peaking at a high frequency without increasing the size of the die area and/or the power supply level.
Non-uniform quantized feedback in federated learning
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a client device may determine a feedback associated with a machine learning component based at least in part on applying the machine learning component. Accordingly, the client device may transmit a quantized value based at least in part on the feedback. The quantized value is determined based at least in part on distances between the feedback and a non-uniform set of quantized digits. Numerous other aspects are provided.
Decision feedback equalizer and a device including the same
A decision feedback equalizer including: a first input latch configured to generate a first output signal from first data received by the first input latch, wherein the first input latch includes: a first sub-circuit configured to receive the first data and a reference voltage, compare the first data and the reference voltage, and generate first internal signals having different transition timings according to a result of the comparison between the first data and the reference voltage; and a second sub-circuit configured to receive, as first feedback, a second output signal, which corresponds to second data received by the first latch earlier than the first data, and generate the first output signal, which compensates for a difference between the transition timings of the first internal signals, based on the first feedback.
Asymetric decision feedback equalization
Systems and methods for implementation of modified decision feedback equalization. In one embodiment, a method, includes sweeping a reference voltage signal across a set of voltages to find a center point of an eye diagram, determining whether an asymmetry is present in the eye diagram relative to the center point of the eye diagram, and when an asymmetry is determined to be present, generating a control signal to select a mode of decision feedback equalization to be applied to an input data bit.
Analog Channel Equalization and Channel Adaptation
A receiver circuit including mechanisms for analog channel equalization and channel adaptation is disclosed. The receiver includes a front-end circuit configured to generate a filtered signal by performing filtering of an incoming signal that includes a stream of data symbols. A sample recovery circuit configured to sample an equalized signal, based on the filtered signal, to generate a plurality of recovered data symbols. A decision feedback equalization (DFE) circuit configured to generate the feedback signal based on the plurality of recovered data symbols. A logic circuit is configured to cause adjustment to one or more filters in the front-end circuit based on the plurality of recovered data symbols.
LIVE OFFSET CANCELLATION OF THE DECISION FEEDBACK EQUALIZATION DATA SLICERS
A receiver utilizes loop-unrolled decision feedback equalization (DFE). For each sample, two comparators, each configured with different thresholds, sample an input signal. The output of one of these comparators is selected and used as the output of the receiver and may be optionally input to additional DFE circuitry. The output of the other (non-selected) comparator is used to adjust an input offset voltage of that same comparator. Adjustments to the offset voltages of the comparators may be based on a statistical analysis of the respective outputs of the two comparators when not selected. Adjustments to the offset voltages of the comparators may be based on comparisons between the respective outputs of the two comparators when not selected to the outputs of a reference comparator that has been calibrated for minimal or zero offset.
High speed digital data transmission
A receiver circuit includes an analog front end and a non-linear equalizer. The analog front end including a super source follower (SSF) amplifier having a first input terminal adapted to couple to a transmission line to receive an input signal referenced to a first voltage level, a second input adapted to receive a reference voltage, and first and second output terminals adapted to provide an amplified signal referenced to a second voltage level. The non-linear equalizer coupled to receive an output signal of the analog front end and compensate for inter-symbol interference at a data rate of at least 14 Gbps. The SSF amplifier includes transistors having relative sizes selected to provide a frequency response of the SSF amplifier with a peak at a frequency approximately ⅔ of the data rate.