An adaptive Log-likelihood Ratio compression algorithm for Downlink Shared Channel processing in LTE receiver

Author

Anton, Lucian ; Haechul Lee ; Chaehag Yi

Author_Institution

Modem & Connectivity Dev. Team, Samsung Electron., Yongin, South Korea

fYear

2013

fDate

17-19 Nov. 2013

Firstpage

1

Lastpage

4

Abstract

In high data rate communication systems using a Hybrid Automatic Repeat Request, Log-likelihood Ratio (LLR) values should be handled effectively and optimally for reducing memory size. In the paper an adaptive compression algorithm for LLR values is proposed. The approach is based on a dynamic two-dimensional quantization principle and a Huffman encoding. The algorithm was verified for QPSK, 16QAM and 64QAM modulations. Simulation results show a relatively low performance degradation (within 0.5 dB at low SNR range) when a constraint of 2.4 bits per LLR is applied.

Keywords

Huffman codes; Long Term Evolution; automatic repeat request; data compression; quadrature amplitude modulation; quadrature phase shift keying; quantisation (signal); radio receivers; statistical testing; wireless channels; 16QAM modulation; 64QAM modulation; HARQ; Huffman encoding; LLR values; LTE receiver; Long Term Evolution; PDSCH; QPSK modulation; adaptive log-likelihood ratio compression algorithm; dynamic 2D quantization principle; high data rate communication systems; hybrid automatic repeat request; memory size reduction; physical downlink shared channel processing; Decoding; Phase shift keying; Quantization (signal); Receivers; Signal to noise ratio; Vectors; HARQ; LLR; LTE; OFDM; compression;

fLanguage

English

Publisher

ieee

Conference_Titel

SoC Design Conference (ISOCC), 2013 International

Conference_Location

Busan

Type

conf

DOI

10.1109/ISOCC.2013.6864015

Filename

6864015