H04L2025/03681

Methods and circuits for adaptive equalization
09985806 · 2018-05-29 · ·

An integrated circuit equalizes a data signal expressed as a series of symbols. The symbols form data patterns with different frequency components. By considering these patterns, the integrated circuit can experiment with equalization settings specific to a subset of the frequency components, thereby finding an equalization control setting that optimizes equalization. Optimization can be accomplished by setting the equalizer to maximize symbol amplitude.

Fixed-point conjugate gradient digital pre-distortion (DPD) adaptation
09749161 · 2017-08-29 · ·

A predistortion method and apparatus are provided which use a DPD actuator (225) to apply a memory polynomial formed with first DPD coefficients to a first input signal x[n], thereby generating a first pre-distorted input signal y[n] which is provided to the non-linear electronic device (253) to produce the output signal, where the memory polynomial may be adaptively modified with a digital predistortion adapter (224) which computes second DPD coefficients u[n] with an iterative fixed-point conjugate gradient method which uses N received digital samples of the first pre-distorted input signal y[n] and a feedback signal z[n] captured from the output signal to process a set of conjugate gradient parameters (u, b, v, r, , , ) at each predetermined interval, thereby updating the first DPD coefficients with the second DPD coefficients u[n] generate a second pre-distorted input signal which is provided to the non-linear electronic device.

Decision feedback equalizers and operating methods thereof

A decision feedback equalizer (DFE) includes a sampler for receiving a first input signal and comparing an amplitude of the first input signal with a first predetermined voltage level and a second predetermined voltage level. The DFE includes a DFE logic circuit for receiving at least one first sign signal based on comparison results, and for selectively updating a tap coefficient based on the at least one first sign signal. The DFE logic circuit is configured to update the tap coefficient when the at least one first sign signal indicates the amplitude of the first input signal is not between the first predetermined voltage level and the second predetermined voltage level. The DFE logic circuit is configured to maintain the tap coefficient when the at least one first sign signal indicates the amplitude of the first input signal is between the first and the second predetermined voltage levels.

Methods and Circuits for Adaptive Equalization
20170180163 · 2017-06-22 ·

An integrated circuit equalizes a data signal expressed as a series of symbols. The symbols form data patterns with different frequency components. By considering these patterns, the integrated circuit can experiment with equalization settings specific to a subset of the frequency components, thereby finding an equalization control setting that optimizes equalization. Optimization can be accomplished by setting the equalizer to maximize symbol amplitude.

Adaptive equalization circuit, digital coherent receiver, and adaptive equalization method

A circuit includes a calculation circuit configured to calculate a noise power of a predetermined-training-sequence pattern repeatedly included in a first signal input into an adaptive equalizer, based on a second signal obtained by compensating the first signal by a compensation circuit, a channel-estimation value based on the second signal, and the predetermined-training-sequence pattern; and an average circuit configured to obtain an average value of estimation values of frequency offsets based on the predetermined-training-sequence pattern having the noise power equal to or smaller than a predetermined power, among estimation values of frequency offsets based on the predetermined-training-sequence pattern, wherein the compensation circuit is configured to compensate a frequency offset of the predetermined-training sequence pattern based on the average value and thereby obtain the second signal, and the adaptive equalizer is configured to perform adaptive-equalization processing of the first signal with a setting value based on the second signal.

Updating a filter of an equalizer
09674010 · 2017-06-06 · ·

In one aspect, a tuner includes an analog front end to receive a radio frequency (RF) signal and to downconvert the RF signal to a second frequency signal, a digitizer to convert the second frequency signal to a digitized signal, a channel equalizer including a filter to filter the digitized signal, and a first controller to update the filter according to a frequency response of the filter.

Transmission apparatus
09667343 · 2017-05-30 · ·

A transmission apparatus of a receiving side to receive a signal transmitted from a transmission apparatus of a transmitting side, the transmission apparatus of the receiving side includes: a first monitor configured to measure an eye pattern indicating a signal waveform transition of the signal transmitted from the transmission apparatus of the transmitting side; a pattern analyzer configured to extract a first feature of the eye pattern measured by the first monitor; and a regulation controller configured to cause the transmission apparatus of the transmitting side to adjust at least one of rising and falling of a signal to be transmitted, based on the first feature extracted by the pattern analyzer.

Power Aware Receiver/Transmitter Adaptation for High Speed Serial Interfaces
20170085400 · 2017-03-23 ·

A receiver includes first and second equalization modules adapted to provide first and second compensations to a data signal, and a control module including a list that identifies the first equalization module as being less efficient than the second. The control module provides first and second compensation levels of the first and second compensations, such that the first and second compensations operate on the data signal to meet a bit error rate (BER) target, lowers the first compensation to reduce the power consumption of the receiver based on the list, and determines whether, in response to an increase in the level of the second compensation the BER target is met.

ADAPTIVE EQUALIZATION CIRCUIT, DIGITAL COHERENT RECEIVER, AND ADAPTIVE EQUALIZATION METHOD

A circuit includes a calculation circuit configured to calculate a noise power of a predetermined-training-sequence pattern repeatedly included in a first signal input into an adaptive equalizer, based on a second signal obtained by compensating the first signal by a compensation circuit, a channel-estimation value based on the second signal, and the predetermined-training-sequence pattern; and an average circuit configured to obtain an average value of estimation values of frequency offsets based on the predetermined-training-sequence pattern having the noise power equal to or smaller than a predetermined power, among estimation values of frequency offsets based on the predetermined-training-sequence pattern, wherein the compensation circuit is configured to compensate a frequency offset of the predetermined-training sequence pattern based on the average value and thereby obtain the second signal, and the adaptive equalizer is configured to perform adaptive-equalization processing of the first signal with a setting value based on the second signal.

Methods and circuits for adaptive equalization
09544170 · 2017-01-10 · ·

An integrated circuit equalizes a data signal expressed as a series of symbols. The symbols form data patterns with different frequency components. By considering these patterns, the integrated circuit can experiment with equalization settings specific to a subset of the frequency components, thereby finding an equalization control setting that optimizes equalization. Optimization can be accomplished by setting the equalizer to maximize symbol amplitude.