Patent classifications
H04L25/03885
CONTINUOUS TIME LINEAR EQUALIZATION AND BANDWIDTH ADAPTATION USING ASYNCHRONOUS SAMPLING
Methods and systems are described for generating a time-varying information signal at an output of a continuous time linear equalizer (CTLE), asynchronously sampling a data signal according to a sampling clock having a frequency less than a data rate of the data signal; generating corresponding pattern-verified samples for at least two data patterns, each of the at least two data patterns having a respective frequency content; determining corresponding frequency-specific voltage measurements associated with each of the at least two data patterns based on the corresponding pattern-verified samples of the at least two data patterns; and adjusting an equalization of the data signal based on a comparison of the corresponding frequency-specific voltage measurements.
RECEIVER DEVICE AND RECEPTION METHOD
A receiver device according to an embodiment includes a equalizer, a sampler, and a controller. The equalizer receive a first signal. The equalizer boosts the first signal to output a resultant as a second signal. The sampler samples the second signal. The sampler outputs a sampling result of the second signal as a first digital signal. The controller executes adaptive processing for adapting an amount of boost of the first signal. In the adaptive processing, the controller is configured to: adjust an amount of boost for the equalizer based on inter-symbol interference of a part in the first digital signal, the part matching a data pattern of a set pattern filter; and dynamically change a pattern filter to be set according to the amount of boost for the equalizer.
Systems and methods to mitigate electro-magnetic interference in single twisted-pair-based communication systems
A transceiver to communicate in a vehicle via a single twisted-pair Ethernet cable includes a transmitter to transmit signals via the single twisted-pair Ethernet cable and a receiver to receive signals via the single twisted-pair Ethernet cable. The transceiver includes an equalizer, a signal-to-noise ratio estimator, and a controller. The equalizer includes a notch filter and a slicer. The equalizer receives an input signal received by the transceiver via the single twisted-pair Ethernet cable. The notch filter cancels electromagnetic interference from the input signal and to output a filtered signal. The slicer slices the filtered signal. The signal-to-noise ratio estimator estimates a signal-to-noise ratio based on an output of the slicer. The controller controls a rate of adapting the equalizer by controlling a rate of change of tap values of the notch filter based on the signal-to-noise ratio.
METHOD, APPARATUS, AND SYSTEM FOR SIGNAL EQUALIZATION
Aspects of the embodiments are directed to systems, methods, and apparatuses to determine transmission equalization coefficients (TxEQs) for one or more lanes of a high speed serial link. Embodiments include determining a jitter tolerance for each TxEQ of a plurality of TxEQs for a lane of the link. The jitter tolerance for each TxEQ for the lane is based on a level of jitter induced on the lane to detect a number of errors on the lane; determining a voltage (VOC) margin for each TxEQ for the lane, wherein the voltage margin for the lane is based on a voltage corners test applied to the lane to detect a number of errors on the lane at a high voltage point and a low voltage point; determining a TxEQ that provides maximum jitter tolerance and based on the determined lowest voltage margin; and using the TxEQ for the lane during operation.
Wireless communication device, wireless communication system, and wireless communication method
A wireless communication device includes an estimation observation unit that observes a channel condition by estimating a tendency of a long delay wave and a channel fluctuation from a received signal in which a training signal is added to a data frame, a first equalizer that compensates for the received signal, a second equalizer that compensates for the received signal with a property of having a higher long delay wave tolerance and a lower channel fluctuation tolerance than the first equalizer, and a control unit that performs control which switches such that the first equalizer or the second equalizer performs compensation for the received signal, on the basis of the channel condition observed by the estimation observation unit.
Equalization in high-speed data channel having sparse impulse response
A physical layer transceiver, for connecting a host device to a wireline channel medium that is divided into a total number of link segments, includes a host interface for coupling to a host device, a line interface for coupling to the wireline channel medium, and feed-forward equalization (FFE) circuitry operatively coupled to the line interface to add back, into a signal, components that were scattered in time. Respective individual filter segments are selectably configurable, by adjustment of respective delay lines, to correspond to respective individual link segments. The FFE circuitry also includes control circuitry configured to detect a signal energy peak in at least one particular link segment and, upon detection of the signal energy peak in the particular link segment, configure a respective one of the respective individual filter segments, by adjustment of a respective delay line, to correspond to the respective particular link segment.
Receiver and automatic offset cancellation method thereof
The disclosure provides a receiver and an automatic offset cancellation (AOC) method thereof. The receiver includes a receiving channel circuit and an AOC circuit. The receiving channel circuit generates an equalized differential signal including an equalized first-end signal and an equalized second-end signal according to an input differential signal. The AOC circuit detects a peak of the equalized first-end signal to generate a first peak detection result. The AOC circuit detects a peak of the equalized second-end signal to generate a second peak detection result. The AOC circuit compares the first peak detection result with the second peak detection result to generate a comparison result. The AOC circuit compensates a mismatch of an input differential pair in the receiving channel circuit according to the comparison result.
High speed communications system
Transmission of baseband and carrier-modulated vector codewords, using a plurality of encoders, each encoder configured to receive information bits and to generate a set of baseband-encoded symbols representing a vector codeword; one or more modulation circuits, each modulation circuit configured to operate on a corresponding set of baseband-encoded symbols, and using a respective unique carrier frequency, to generate a set of carrier-modulated encoded symbols; and, a summation circuit configured to generate a set of wire-specific outputs, each wire-specific output representing a sum of respective symbols of the carrier-modulated encoded symbols and at least one set of baseband-encoded symbols.
DIGITAL SIGNAL PROCESSOR, DIGITAL OPTICAL RECEIVER USING THE SAME, AND DIGITAL SIGNAL PROCESSING METHOD
It is difficult to obtain a demodulated signal with high signal quality in a digital optical receiver because it is difficult to compensate for each of different types of waveform distortion by a high-performance equalization process; therefore, a digital signal processor according to an exemplary aspect of the present invention includes a fixed equalization means for performing a distortion compensation process based on a fixed equalization coefficient on an input digital signal; an adaptive equalization means for performing an adaptive distortion compensation process based on an adaptive equalization coefficient on an equalized digital signal output by the fixed equalization means; a low-speed signal generation means for generating a low-speed digital signal by intermittently extracting one of the input digital signal and the equalized digital signal; a low-speed equalization coefficient calculation means for calculating a low-speed equalization coefficient to be used for a distortion compensation process of the low-speed digital signal; and a fixed equalization coefficient calculation means for calculating the fixed equalization coefficient by using at least a predetermined coefficient out of the low-speed equalization coefficient and the predetermined coefficient.
Clock data recovery with decision feedback equalization
Methods and systems are described for generating two comparator outputs by comparing a received signal to a first threshold and a second threshold according to a sampling clock, the first and second thresholds determined by an estimated amount of inter-symbol interference on a multi-wire bus, selecting one of the two comparator outputs as a data decision, the selection based on at least one prior data decision, and selecting one of the two comparator outputs as a phase-error decision, the phase error decision selected in response to identification of a predetermined data decision pattern.