EP-4250652-B1 - ERROR DETECTION AND CORRECTION DEVICE CAPABLE OF DETECTING HEAD POSITION OF SUSPICIOUS ERROR AND PERFORMING FORWARD ERROR PROPAGATION PATH TRACKING FOR PROVIDING INFORMATION NEEDED BY FOLLOW-UP ERROR CORRECTION AND ASSOCIATED METHOD

EP4250652B1EP 4250652 B1EP4250652 B1EP 4250652B1EP-4250652-B1

Inventors

WENG, DENG-FU
LIU, YU-TING
CHIANG, CHE-YU
TSAI, CHUNG-HSIEN
WENG, Huai-Mao

Dates

Publication Date: 20260506
Application Date: 20230316

Claims (13)

An error detection and correction device (100) comprising: a decision-feedback equalizer, DFE, (104) configured to equalize a data signal to generate a first equalized signal; a decision circuit (108), configured to perform hard decision upon the first equalized signal to generate a symbol decision signal; an error detection circuit (126), configured to perform forward error detection at symbol positions of consecutive symbols included in the symbol decision signal to detect a head position of suspicious error that affects at least one symbol in the symbol decision signal; and an error correction circuit (128), configured to perform error correction upon the symbol decision signal in response to the head position of the suspicious error that is detected by the error detection circuit (126); wherein the error correction circuit (128) is configured to perform forward error propagation path tracking that starts from the head position detected by the error detection circuit (126), for selecting an error propagation path with a propagation length; and the error correction is performed according to at least the propagation length.
The error detection and correction device (100) of claim 1, further comprising: a feed-forward equalizer, FFE, (102) configured to process a received signal to generate a second equalized signal as the data signal.
The error detection and correction device (100) of claim 1, wherein the suspicious error detected by the error detection circuit (126) is a single error that affects only a single symbol included in the symbol decision signal; or wherein the suspicious error detected by the error detection circuit (126) is a burst error that affects more than one symbol included in the symbol decision signal.
The error detection and correction device (100) of claim 1, wherein the data signal is derived from a pulse amplitude modulation, PAM, signal.
The error detection and correction device (100) of claim 4, wherein the consecutive symbols comprise a previous symbol at a previous symbol position and a current symbol at a current symbol position; the first equalized signal comprises a previous sample and a current sample, where the previous symbol is a hard decision result of the previous sample, and the current symbol is a hard decision result of the current sample; and the error detection circuit (126) performs the forward error detection by checking if: an absolute difference between the previous sample and the previous symbol is not larger than a predetermined threshold; an absolute difference between the current sample and the current symbol is larger than the predetermined threshold; and an absolute value of the current sample is smaller than a maximum PAM level.
The error detection and correction device (100) of claim 1, wherein the error detection circuit (126) is further configured to control activation of the error correction circuit (128) during the forward error detection.
The error detection and correction device (100) of claim 6, wherein the error correction circuit (128) is activated in response to the head position of the suspicious error being detected by the error detection circuit (126).
An error detection and correction method comprising: performing decision-feedback equalization upon a data signal to generate a first equalized signal; performing hard decision upon the first equalized signal to generate a symbol decision signal; performing forward error detection at symbol positions of consecutive symbols included in the symbol decision signal to detect a head position of suspicious error that affects at least one symbol in the symbol decision signal; and performing error correction upon the symbol decision signal in response to the head position of the suspicious error, comprising: performing forward error propagation path tracking that starts from the head position, for selecting an error propagation path with a propagation length; and performing the error correction according to at least the propagation length.
The error detection and correction method of claim 8, further comprising: performing feed-forward equalization upon a received signal to generate a second equalized signal as the data signal.
The error detection and correction method of claim 8, wherein the suspicious error is a single error that affects only a single symbol included in the symbol decision signal; or wherein the suspicious error is a burst error that affects more than one symbol included in the symbol decision signal.
The error detection and correction method of claim 8, wherein the data signal is derived from a pulse amplitude modulation, PAM, signal.
The error detection and correction method of claim 11, wherein the consecutive symbols comprise a previous symbol at a previous symbol position and a current symbol at a current symbol position; the first equalized signal comprises a previous sample and a current sample, where the previous symbol is a hard decision result of the previous sample, and the current symbol is a hard decision result of the current sample; and performing the forward error detection comprises: checking if: an absolute difference between the previous sample and the previous symbol is not larger than a predetermined threshold; an absolute difference between the current sample and the current symbol is larger than the predetermined threshold; and an absolute value of the current sample is smaller than a maximum PAM level.
The error detection and correction method of claim 8, wherein performing the forward error detection further comprises: controlling activation of the error correction during the forward error detection.

Description

This application claims the benefit of U.S. Provisional Application No. 63/323,118, filed on March 24th, 2022. Background The present invention relates to data communications, and more particularly, to an error detection and correction device capable of detecting a head position of suspicious error and performing forward error propagation path tracking for providing information needed by follow-up error correction and an associated method. In high speed data communication systems, existing filtering and equalization schemes may not be enough to support challenging channels and next-generation Ethernet. For example, the detection of the received signal in a data communication system is challenging due to several factors such as noise, cross-talk, and inter-symbol interference (ISI). A typical decision-feedback equalizer (DFE) can remove the post-cursor ISI by using one or more previous symbols (e.g., one or more previous hard decisions) . However, error propagation may be induced by the typical DFE due to the feedback characteristic that relies on previous hard decision(s). Maximum likelihood sequence detection (MLSD) is a commonly used technique which utilizes and further removes the ISI to deal with noise. However, MLSD has a higher level of implementation complexity and a higher level of power and memory consumption. In some high-speed Ethernet standards, a simple way called 1+D precoding can use inter-symbol information of DFE to eliminate DFE error propagation. However, it needs a precoding engine in the transmit (TX) side and a deprecating engine in the receive (RX) side. In addition, it causes an additional error after the error propagation terminates, and is unable to eliminate the first random error. Thus, there is a need for a low-cost error eliminator which utilizes inter-symbol information of DFE to compensate not only the propagated errors but also the first random error. US 2019/0372607 A1 describes maximum likelihood error detection for decision feedback equalizers with PAM modulation. EP 3 713 167 A1 discloses an error correction method and an error correction apparatus. Summary One of the objectives of the claimed invention is to provide an error detection and correction device capable of detecting a head position of suspicious error and performing forward error propagation path tracking for providing information needed by follow-up error correction and an associated method. According to a first aspect of the present invention, an exemplary error detection and correction device is disclosed. The exemplary error detection and correction device includes a decision-feedback equalizer (DFE), a decision circuit, an error detection circuit, and an error correction circuit. The DFE is configured to equalize a data signal to generate a first equalized signal. The decision circuit is configured to perform hard decision upon the first equalized signal to generate a symbol decision signal. The error detection circuit is configured to perform forward error detection at symbol positions of consecutive symbols included in the symbol decision signal to detect a head position of suspicious error that affects at least one symbol in the symbol decision signal. The error correction circuit is configured to perform error correction upon the symbol decision signal in response to the head position of the suspicious error that is detected by the error detection circuit, wherein the error correction circuit is configured to perform forward error propagation path tracking that starts from the head position detected by the error detection circuit, for selecting an error propagation path with a propagation length; and the error correction is performed according to at least the propagation length. According to a second aspect of the present invention, an exemplary error detection and correction method is disclosed. The exemplary error detection and correction method includes: performing decision-feedback equalization upon a data signal to generate a first equalized signal; performing hard decision upon the first equalized signal to generate a symbol decision signal; performing forward error detection at symbol positions of consecutive symbols included in the symbol decision signal to detect a head position of suspicious error that affects at least one symbol in the symbol decision signal; and performing error correction upon the symbol decision signal in response to the head position of the suspicious error, comprising: performing forward error propagation path tracking that starts from the head position, for selecting an error propagation path with a propagation length; and performing the error correction according to at least the propagation length. These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. Brief Description o