Method and auxiliary method, apparatus base station and user equipment for interference cancellation

Patent metadata

Field	Value
Publication number	US-10313174-B2
Application number	US-201615545672-A
Country	US
Kind code	B2
Filing date	Jan 25, 2016
Priority date	Jan 23, 2015
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

The present disclosure provides a method for interference cancellation which includes: calculating a mean value and a variance value of a received signal to obtain statistics information of the received signal; calculating an estimating log-likelihood ratio using the statistics information of the received signal; calculating a decoding log-likelihood ratios of the received signal using the estimating log-likelihood ratio of the received signal, and performing calculations to update the statistics information of the received signal; repeating the above steps for a pre-determined number of times, performing hard decisions on the decoding log-likelihood ratios of the received signal, and outputting data bits obtained from the hard decision. The present disclosure also provides an apparatus, an auxiliary method, a base station and a terminal device for interference cancellation. The mechanism of the present disclosure can reduce the impact of inherent interference in the FBMC/OQAM system on system performances, and increase spectral efficiency and design flexibility of the FBMC/OQAM system.

First claim

The invention claimed is:

1. A method for interference cancellation by an apparatus in a mobile communication system, comprising:
calculating a mean value and a variance value of a received signal to obtain statistics information of the received signal;
calculating an estimating log-likelihood ratio of the received signal using the statistics information, based on an initialized signal at a target time-frequency grid point, a source signal at the target time-frequency grid point, and a transmitted real symbol;
calculating a decoding log-likelihood ratio of the received signal using the estimating log-likelihood ratio of the received signal, and updating calculations of the statistics information of the received signal;
repeating calculating the mean value and the variance value, calculating the estimating log-likelihood ratio, and calculating the decoding log-likelihood ratio for a pre-determined number of times, and performing hard decisions on the decoding log-likelihood ratio of the received signal; and
outputting data bits obtained from the hard decisions,
wherein the method further comprises canceling, by the apparatus, inter-symbol interference (ISI) and inter-carrier interference (ICI) in a single input single output (SISO) filter bank multi-carrier (FBMC)/offset quadrature amplitude modulation (OQAM) system or in a multi input multi output (MIMO) FBMC/OQAM system or in a distributed multi-antenna FBMC/OQAM system.

2. The method of claim 1 , wherein
the calculating a mean value and a variance value of a received signal comprises one of:
calculating a mean value and a variance value of the received signal after interference post-processing; and
calculating a mean value and a variance value of the received signal after interference pre-processing.

3. The method of claim 2 , further comprising the following steps to obtain the received signal after interference post-processing:
processing the received signal through matched filtering, channel equalization, synthesizing, and taking real part to obtain an initialized signal;
processing the initialized signal through symbol-level hard decisions based on minimum Euclidean distance to obtain a hard decision signal;
processing the hard decision signal through demodulation, parallel to serial conversion, de-interleaving and channel decoding to obtain a processed signal, processing the processed signal through channel encoding, interleaving, serial to parallel conversion, QAM modulation and taking real/imaginary part to obtain an estimated signal; and
performing initial interference cancellation using the initialized signal and the estimated signal to obtain the received signal after the interference post-processing.

4. The method of claim 3 , wherein the initial interference cancellation is expressed as:

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Assignees

• Samsung Electronics Co Ltd

Inventors

• Zhu Dalin
• Yu Bin
• Sun Pengfei

Classifications

• H04L27/2647

  Arrangements specific to the receiver only (equalisation H04L27/01) · CPC title

• H04B7/0452

  Multi-user MIMO systems · CPC title

• H04L27/2615

  Reduction thereof using coding · CPC title

• H04L27/366

  Arrangements for compensating undesirable properties of the transmission path between the modulator and the demodulator · CPC title

• H04L1/0054

  Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms · CPC title