A signaling circuit having a selectable-tap equalizer. The signaling circuit includes a buffer, a select circuit and an equalizing circuit. The buffer is used to store a plurality of data values that correspond to data signals transmitted on a signaling path during a first time interval. The select circuit is coupled to the buffer to select a subset of data values from the plurality of data values according to a select value. The equalizing circuit is coupled to receive the subset of data values from the select circuit and is adapted to adjust, according to the subset of data values, a signal level that corresponds to a data signal transmitted on the signaling path during a second time interval.

A signal processing device includes: a filter configured to perform an adaptive equalization process of a signal, on a basis of a filter coefficient; an updater configured to update the filter coefficient, on a basis of amplitude of the signal and a target value of the amplitude; and a corrector configured to correct the target value, on a basis of the amplitude of the signal.

An equalizer tuning method for a memory storage device is provided according to an exemplary embodiment of the disclosure. The method includes: receiving a first signal; modulating the first signal by a first modulation circuit according to a first type parameter and modulating the first signal by a second modulation circuit according to a second type parameter; detecting a signal eye-width value and a signal eye-height value of the modulated first signal; and adjusting the first type parameter according to the detected signal eye-width value and adjusting the second type parameter according to the detected signal eye-height value.

A method and structure for equalization in coherent optical receivers. Block-based LMS (BLMS) algorithm is one of the many efficient adaptive equalization algorithms used to (i) increase convergence speed and (ii) reduce implementation complexity. Since the computation of the equalizer output and the gradient of the error are obtained using a linear convolution, BLMS can be efficiently implemented in the frequency domain with the constrained frequency-domain BLMS (FBLMS) adaptive algorithm. The present invention introduces a novel reduced complexity constrained FBLMS algorithm. This new approach replaces the two discrete Fourier transform (DFT) stages required to evaluate the DFT of the gradient error, by a simple frequency domain filtering. Implementation complexity can be drastically reduced in comparison to the standard constrained FBLMS. Furthermore, the new approach achieves better performance than that obtained with the unconstrained FBLMS in ultra-high speed coherent optical receivers.

A user equipment (UE) for channel estimation in a high-speed single-frequency network (HS-SFN) is provided. The UE includes at least one non-transitory computer-readable medium; and at least one processor, which, when executing instructions stored on the at least one non-transitory computer-readable medium, causes the UE to perform a method including calculating an estimated frequency offset (FO) correction for a received signal using at least an FO estimation generated by an automatic frequency control (AFC) module using at least a previously-calculated channel estimate output from a channel estimator (CE) as input in a first feedback loop; and calculating, by the CE, a current channel estimate using at least the received signal adjusted by the estimated FO correction from the first feedback loop and one or more channel parameter estimates generated by the AFC using at least the previously-calculated channel estimate output from the CE as input in a second feedback loop.

A receiver applies a calibration method to compensate for skew between input channels. The receiver skew is estimated by observing the coefficients of an adaptive equalizer which adjusts the coefficients based on time-varying properties of the multi-channel input signal. The receiver skew is compensated by programming the phase of the sampling clocks for the different channels. Furthermore, during real-time operation of the receiver, channel diagnostics is performed to automatically estimate differential group delay and/or other channel characteristics based on the equalizer coefficients using a frequency averaging or polarization averaging approach. Framer information can furthermore be utilized to estimate differential group delay that is an integer multiple of the symbol rate. Additionally, a DSP reset may be performed when substantial signal degradation is detected based on the channel diagnostics information.

A high-speed serial data interface includes a transmitter and a receiver. The transmitter includes a feed-forward equalization (FFE) module. The FFE module has a main tap and at least one secondary tap. In a first mode, a sum of absolute values of a main tap compensation value and a secondary tap compensation value of each one of the at least one secondary tap is equal to one. In a second mode, the main tap compensation value has a unity gain equal to one, and each secondary tap compensation value is greater than or equal to the secondary tap compensation value in the first mode divided by the main tap compensation value in the first mode.

An equalizer circuit includes: an addition circuit configured to add an input signal and a compensation signal; a comparison circuit configured to compare an output signal of the addition circuit; a plurality of first latch circuits configured to hold an output signal of the comparison circuit, the plurality of first latch circuits being connected in cascade; a selection circuit configured to select and output one of output signals of the comparison circuit and the plurality of first latch circuits; a second latch circuit configured to hold an output signal of the selection circuit; and a digital analog conversion circuit configured to generate the compensation signal, based on an output signal of the second latch circuit.

A serial transmitter that outputs one symbol every unit interval (UI) from a data source is presented. The serial transmitter includes a serial output port that outputs one symbol every unit interval (UI) from a data source. The serial transmitter also includes a plurality of driver segments that jointly drive the serial output port. Each driver segment is configured to use one of N phases of a sampling clock to serialize and transmit data from the data source. Different sets of the driver segments are configured to use different phases of the sampling clock for serializing and transmitting data, the sampling clock being a half-rate clock having a period of two UI.

A device includes a first terminal configured to receive a reference voltage, a second terminal configured to receive a weighted tap value, a local generator circuit configured to create a group of unsigned voltage correction values based on the reference voltage and the weighted tap value, and a sign configuring circuit configured to receive the group of unsigned voltage correction values from the local generator circuit and assign a polarity to each respective unsigned voltage correction value of the group of unsigned voltage correction values, creating correction signals from the group of unsigned voltage correction values. The device also includes an output configured to transmit the correction signals to a first input of a processing circuit, wherein the processing circuit is configured to use the correction signals to offset inter-symbol interference from a data stream on a distorted bit based at least on a control signal.