H04L25/4917

Methods, systems and apparatus for hybrid signal processing for pulse amplitude modulation

A method to implement hybrid signal processing includes steps for receiving an analog signal at a receiver frontend, sampling the received analog signal and storing the analog sampled signals using a plurality of sampling circuitries inside the receiver frontend. Then, processing the plurality of analog sampled signals using interleaved feed-forward equalizers (FFEs) to provide FFE interleaved sampled signal values corresponding to each of the sampling circuitries. Then, processing the analog sampled signals at an interleaved Decision Feedback Equalizer (DFE) to obtain DFE interleaved sampled signal values, summing each of the FFE interleaved sampled signal values with output from one of the DFE interleaved sampled signal values to provide equalizer output signal values, and digitizing the equalizer output signal values to provide digital data bits corresponding to each of the equalizer output signal values. Implementations of the method as a hybrid communication system, system-on-a-chip, and computer readable memory are also disclosed.

Recording apparatus, recording method, reproduction apparatus, reproduction method, recording medium, encoding apparatus, and decoding apparatus
11521651 · 2022-12-06 · ·

There is provided a recording apparatus, a recording method, a reproduction apparatus, a reproduction method, a recording medium, an encoding apparatus, and a decoding apparatus which enable recording or reproduction to be easily implemented at high line density. User data is encoded into a multilevel edge code, and a multilevel code whose value changes in accordance with the multilevel edge code is recorded. The multilevel edge code is generated through state transition of a code generation model which includes a state representing the number of times that zero is consecutive corresponding to a number of ways of the number of times that zero is consecutive, which is the number of times that an edge of 0 is consecutive among edges representing a change amount from an immediately preceding value of the multilevel code of an ML value which is equal to or greater than 3, and which transitions to a state representing the number of times that zero is consecutive including 0 in a case where 0 is output, and transitions to a state representing that the number of times that zero is consecutive is 0 times in a case where one of 1 to ML−1 is output.

Digital noise-shaping FFE/DFE for ADC-based wireline links
11522735 · 2022-12-06 · ·

Apparatus and associated methods relate to an ADC-based digital receiver including a feedforward equalizer (FFE) that has m precursor taps and n postcursor taps to equalize the precursor portion, and to adapt postcursor intersymbol interference (ISI) through a predetermined equalization coefficient selected to counteract the noise boosting effect associated with the precursor equalization. In an illustrative example, the receiver may dynamically balance noise and ISI through adaptively determining a coefficient hp.sub.1 of a first postcursor tap of a first FFE and a coefficient h.sub.1 of a first postcursor tap of a second equalizer adapted to substantially reduce or eliminate additional ISI introduced by the first FFE. The first FFE may optimize ISI removal and noise reduction, for example. One of the coefficients h.sub.1 and hp.sub.1 may be predetermined, and then the other coefficient may be iteratively adapted to trade off precursor ISI and postcursor ISI to minimize BER.

ADAPTIVE NON-SPECULATIVE DFE WITH EXTENDED TIME CONSTRAINT FOR PAM-4 RECEIVER
20220376958 · 2022-11-24 · ·

The present disclosure proposes an adaptive non-speculative DFE with an extended time constraint for a PAM-4 receiver and a method for operating the same. An adaptive non-speculative DFE with an extended time constraint for a PAM-4 receiver according to the present disclosure comprises a Continuous-Time Linear Equalizer (CTLE) to boost high-frequency components of an input signal, a Track and Hold (T&H) circuit to track and hold an output of the CTLE, and a sampler, wherein the sampler includes a Decision Feedback Equalization (DFE) sampler to equalize an output of the T&H circuit and sample an output of the T&H circuit in a DFE sampling clock phase; and a DATA sampler to sample a signal equalized by the DFE sampler in a DATA sampling clock phase, wherein the DFE sampling clock phase differs from the DATA sampling clock phase.

MASKED TRAINING AND ANALYSIS WITH A MEMORY ARRAY
20230057441 · 2023-02-23 ·

Methods, systems, and devices for masked training and analysis with a memory array are described. A memory device may operate in a first mode in which a maximum transition avoidance (MTA) decoder for a memory array of the memory device is disabled. During the first mode, the memory device may couple an input node of the MTA decoder with a first output node of a first decoder, such as a first pulse amplitude modulation (PAM) decoder. The memory device may operate in a second mode in which the MTA decoder for the memory array is enabled. During the second mode, the memory device may couple the input node of the MTA decoder with a second output node of a second decoder, such as a second PAM decoder.

Memory device for generating pulse amplitude modulation-based DQ signal and memory system including the same

A memory device includes a memory cell array and a transmitter, wherein the transmitter includes a pulse amplitude modulation (PAM) encoder configured to generate a PAM-n first input signal (where n is an integer greater than or equal to 4) from data read from the memory cell array; a pre-driver configured to generate a second input signal based on the first input signal and based on a calibration code signal, and output the second input signal using a first power voltage; and a driver configured to output a PAM-n DQ signal using a second power voltage lower than the first power voltage in response to the second input signal.

Signal receiver and operation method thereof

A signal receiver includes a data sampler receiving a differential input signal having first and second input signals and determining bit values of the differential input signal based on first and second reference voltages, and a reference voltage generator performing a pre-tuning operation and a post-tuning operation to generate the reference voltages. The reference voltage generator performs the pre-tuning operation by generating first and second initial voltages and adjusting one of the initial voltages to generate third and fourth voltages. After the pre-tuning operation, the reference voltage generator performs the post-tuning operation by increasing or decreasing the third voltage to generate the first reference voltage and decreasing or increasing the fourth voltage to generate the second reference voltage based on a comparison result between the third voltage and the first input signal and a second comparison result between the fourth voltage and second input signal.

Channel equalization for multi-level signaling
11502881 · 2022-11-15 · ·

A memory interface may include a transmitter that generates multi-level signals made up of symbols that convey multiple bits of data. The transmitter may include a first data path for a first bit (e.g., a least significant bit (LSB)) in a symbol and a second data path for a second bit (e.g., the most significant bit (MSB)) in the symbol. Each path may include a de-emphasis or pre-emphasis buffer circuit that inverts and delays signals received at the de-emphasis or pre-emphasis buffer circuit. The delayed and inverted data signals may control de-emphasis or pre-emphasis drivers that are configured to apply de-emphasis or pre-emphasis to a multi-level signal.

TRANSMISSION PROCESSING METHOD AND DEVICE

A transmission processing method includes: performing encoding or decoding, or instructing a second communication device to perform encoding or decoding. The encoding or decoding uses a multi-level structure.

CTLE adaptation based on statistical analysis

Optimized continuous time linear equalization (CTLE) circuit parameters for a received signal are found using an iterative search process. The received signal is repeatedly sampled by an analog-to-digital converter (ADC). Certain samples containing interference that cannot be cancelled by a CTLE in the sampled series are filtered out (discarded). The remaining samples are used to generate, over a selected evaluation window, a histogram of the sampled values. This histogram is used to calculate a figure of merit for the current CTLE parameter settings. The figures of merit for various CTLE parameter settings are compared to find the set of CTLE parameter settings that optimize the figure of merit and by extension, optimize the CTLE circuitry's performance at equalizing the received signal.