Marvell International Limited

Marvellworld Trade Ltd.

Jing Fang

Runsheng He

Kok-Wui Cheong

Zhipei Chi

A decoder includes a syndrome calculator, a Key Equation Solver (KES) and an error corrector. The syndrome calculator receives an n-symbol code word encoded using a Reed Solomon (RS) code to include (n&#x2212;k) redundancy symbols, calculates for the code word 2t syndromes Si, t=(n&#x2212;k)/2 is a maximal number of correctable erroneous symbols. The KES derives an error locator polynomial {circumflex over (&#x2003;)}(x) whose roots identify locations of erroneous symbols, by applying to the syndromes a number of t iterations. In each iteration the KES calculates two discrepancies between {circumflex over (&#x2003;)}(x) and respective two candidates of {circumflex over (&#x2003;)}(x), and derives from the two candidates an updated candidate of {circumflex over (&#x2003;)}(x). The error corrector recovers the code word by correcting the erroneous symbols using the derived error locator polynomial {circumflex over (&#x2003;)}(x).

Low-latency decoder for Reed Solomon codes

A method of performing timing recovery in a receiver device includes receiving an oversampled signal corresponding to at least a first portion of a radio frequency signal received by the receiver device from a transmitter device. The oversampled signal is sampled at an oversampling rate that is higher than a baud rate of the receiver device. The method also includes estimating a first timing error using samples of the oversampled signal. Estimating the first timing error includes generating a first timing error signal indicative of the estimated first timing error. The method also includes adjusting, using the first timing error signal, at least one sampling rate at which received signals are sampled in the receiver device.

System and method for timing error estimation

In a method for determining timing information in a receiver, a receiver receives a modulated signal and demodulates the modulated signal using an demodulator to produce a demodulated signal. An analog to digital converter converts the demodulated signal to a digital signal and first and second signals are produced from the digital signal. The first signal is analyzed to determine a first phase difference with respect to different portions of the signal, and the second signal is analyzed to determine a second phase difference with respect to different portions of the second signal. The second signal is a frequency domain representation of at least a portion of the first signal. A joint estimate of a sampling period offset and a carrier frequency offset is generated based on the first phase difference and the second phase difference.

Method and apparatus for joint estimation of carrier frequency offset and sampling frequency offset

Systems, methods, and other embodiments associated with a method for estimating a channel between a wireless transmitter and a wireless receiver are described. According to one embodiment, a method includes receiving a signal that includes non-pilot data that is not known to a receiver of the signal; determining an estimated channel for the signal based, at least in part, on the non-pilot data; processing the signal based, at least in part, on the estimated channel to produce an equalized signal; and decoding the equalized signal to produce output data.

Channel estimation with decision feedback

Systems, apparatus and methods are provided for detecting the mode of a received OFDM signal. A received signal may be correlated with one or more time-delayed version of itself resulting in a set of correlation signals. Each correlation signal may be analyzed for one or more characteristics that can be used to determine the symbol length of the received signal. In order to minimize the number of correlations performed, one or more correlations can be used with varying symbol lengths and a fixed guard interval length. The correlation signals can be processed by filters, and the characteristics of the filtered correlation signals can be analyzed to determine the guard interval length of the received signal. In addition to detecting symbol length, the present invention can be used to detect receiver impairment and perform any appropriate compensations.

Mode detection for DVB receiver

Apparatus and methods relating to channel equalization include a method including: generating a first output signal in a frequency domain based on a communications signal of a channel; determining a first channel response based on the first output signal and one or more pilot signals of the communications signal; generating a first equalized signal based on the first output signal and the first determined channel response; generating a first decision signal based on the first equalized signal; generating an output signal in a time domain based on the first decision signal; determining a second channel response based on the time domain output signal; generating a second output signal in the frequency domain based on the second channel response; generating a second equalized signal based on the first and second output signals and the time domain output signal; and generating a second decision signal based on the second equalized signal.

Channel equalization in receivers

In a method for determining timing information in a receiver, a first signal is analyzed to determine a first phase difference with respect to different portions of the first signal, and a second signal is analyzed to determine a second phase difference with respect to different portions of the second signal. The second signal is a frequency domain representation of at least a portion of the first signal. An indication of a carrier frequency offset and a sampling period offset are generated based on the first phase difference and the second phase difference.

Method and apparatus for estimation of carrier frequency offset and/or sampling frequency offset

Systems and techniques relating to channel equalization in received communications signals are described. In one aspect, a communications signal of a channel is obtained and channel effects are removed from the communications signal by generating one or more time-varying channel response estimates.

Growing community of inventors

San Jose, CA, United States of America

Jing Fang