Marvell International Limited

Adina Matache

Jungwon Lee

Gregory Burd

Zining Wu

Jun Xu

Heng Tang

Aditya Ramamoorthy

Yakun Sun

Leilei Song

Konstantinos Sarrigeorgidis

Raj Mani Misra

Sayandev Mukherjee

Hui-Ling Lou

Jiwoong Choi

Bhaskar Nallapureddy

Leilie Song

Systems and methods are provided for determining a data value for a bit of interest in a received data signal. A closest 0-bit symbol candidate is selected from a plurality of 0-bit symbol candidates using a symbol selection distance approximation. A closest 1-bit symbol candidate is selected from a plurality of 1-bit symbol candidates using the symbol selection distance approximation. A 0-bit distance between the received data signal and the selected 0-bit symbol candidate is determined, and a 1-bit distance between the received data signal and the selected 1-bit symbol candidate is determined. A log likelihood ratio is calculated for the bit of interest using the determined 0-bit distance and the determined 1-bit distance.

Low complexity distance metrics for maximum likelihood receivers

Systems and methods are provided for determining a channel quality indicator (CQI) in a transmission system associated with a diversity transmission scheme. A plurality of independent diversity branches are identified in the diversity transmission scheme. Each one of the independent diversity branches may correspond to a different portion of the effective channel and may include any suitable combination of frequency, time, and/or spatial components of the effective channel or of any wired or wireless paths or combinations of the same. An effective Signal-to-Noise Ratio (SNR) value is computed for each one of the identified independent diversity branches. The computed effective SNR values are combined for the identified independent diversity branches to generate a CQI value.

Method and apparatus for estimating a channel quality indicator (CQI) for multiple input multiple output (MIMO) systems

An apparatus includes a circuit configured to at least one of (i) encode first data to produce encoded data or (ii) decode second data to produce decoded data. The circuit is configured to operate according to a predetermined matrix. The predetermined matrix is represented by a two-dimensional grid of elements. Each element of the predetermined matrix labeled with a hyphen corresponds to a zero matrix. Each element of the predetermined matrix labeled with a number corresponds to a respective cyclic-permutation matrix.

Apparatus for encoding and decoding using sparse matrices

Systems and methods are provided for channel estimation using linear phase estimation. These systems and methods enable improved channel estimation by estimating a linear channel phase between received pilot subcarrier signals. The estimated linear phase can then be removed from the received pilot subcarrier signals. After the estimated linear phase is removed from the received pilot subcarrier signals, a channel response can be estimated. A final estimated channel response can be generated by multiplying the results of the linear channel estimation by the estimated linear phase.

Channel estimation using linear phase estimation

A system including a first receiver that generates a first set of decoded codewords; and a first canceller that cancels, in response to any decoded codeword of the first set of decoded codewords failing CRC and a first decoded codeword from the first set of decoded codewords passing CRC, interference of a first codeword on a second set of codewords which includes the plurality of codewords and excludes the first codeword. The system further includes a second receiver that generates a third set of decoded codewords by decoding the second set of codewords; and a second canceller that cancels, in response to any decoded codeword of the third set of decoded codewords failing CRC and a second decoded codeword from the third set of decoded codewords passing CRC, interference of a second codeword on a fourth set of codewords.

Successive interference cancellation in multiple-input multiple-output receivers

Signal power of a received signal, which has a plurality of preamble sequences associated with sub-carrier signals received from a plurality of sub-carriers, in a cellular Orthogonal Frequency Division Multiplexing system may be estimated by estimating as power for at least one preamble sequence of a signal received at a selected receive antenna. The preamble sequence is associated with a base station and a set of sub-carriers. A differential received signal developed for one of the set of sub-carriers is correlated with a normalized differential transmit signal for the preamble sequence, and the estimate of the power for the at least one preamble sequence is extracted based on the correlation.

Signal power estimation for cellular OFDM systems

An apparatus includes a circuit configured to at least one of (i) encode first data to produce encoded data or (ii) decode second data to produce decoded data. The circuit is configured to operate according to a predetermined matrix. Each element of the predetermined matrix labeled with a hyphen corresponds to a zero matrix. Each element of the predetermined matrix labeled with a number corresponds to a respective cyclic-permutation matrix.

LDPC codes and expansion method

A system including a first receiver module and a first interference canceller module. The first receiver module generates a first set of decoded codewords by decoding codewords in a received signal and determines if any of the first set of decoded codewords fails cyclic redundancy check (CRC). The first interference canceller module generates a second signal based on a first decoded codeword from the first set of decoded codewords when (i) any of the first set of decoded codewords fails CRC and (ii) the first decoded codeword passes CRC. By subtracting the second signal from the first signal, the first interference canceller module (i) cancels interference of a first codeword, which corresponds to the first decoded codeword, on a second set of codewords, which includes the plurality of codewords and excludes the first codeword and (ii) generates a third signal, which includes the second set of codewords.

Multiple-input multiple-output receivers using successive interference cancellation based on cyclic redundancy check

A communications device including a low-density parity check (LDPC) encoder and a transmitter. The LDPC encoder is configured to (i) receive data, and (ii) in response to the received data, generate encoded data using a predetermined LDPC matrix, in which the predetermined LDPC matrix is specified by a predetermined base matrix. The transmitter is configured to transmit the encoded data over a communications channel.

Methods and apparatus are provided for utilizing early stopping rules for non-binary turbo codes. Data can be received from a channel and decoded using a non-binary turbo code to generate extrinsic information and a posteriori information. The generated extrinsic information can be evaluated using an early stopping rule. A hard decision on a value of the received data can be made using the a posteriori information if the early stopping rule is satisfied.

Early stopping rules for non-binary turbo codes

A multiple-input multiple-output (MIMO) transmitter including a scrambler and a forward error correction encoder. The scrambler is configured to receive user data and generate scrambled data in response to the user data. The forward error correction encoder is configured to generate encoded data, in response to the scrambled data, using a low density parity check (LDPC) matrix, wherein the LDPC matrix is derived from a specified base matrix.

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Mountain View, CA, United States of America

Adina Matache