Optimal turbo decoding metric generation in a pilot assisted coherent wireless communication system

Author

Ling, Fuyun

Author_Institution

Qualcomm Inc., San Diego, CA, USA

Volume

1

fYear

2000

fDate

2000

Firstpage

298

Abstract

In this paper, we derive the exact expressions of the log-likelihood ratio (LLR) values generated from coherent demodulation using the channel coefficient estimated based on the pilot signal. These results are obtained based on the analytical results given in Ling (1999). It is shown that for Rayleigh fading channels, the LLR values for turbo decoding are the scaled dot products of the channel estimate and the sample of the coded bits. Examples of the computation of the LLR values are given. Considerations and principles for practical implementations are discussed. Simulation results are provided to demonstrate the importance of choosing the proper scaling factor in achieving optimal decoding performance

Keywords

Rayleigh channels; channel coding; decoding; demodulation; land mobile radio; turbo codes; LLR values; Rayleigh fading channels; channel coefficient; coherent demodulation; log-likelihood ratio; mobile radio; optimal turbo decoding metric generation; pilot assisted coherent wireless communication system; scaled dot products; scaling factor; 3G mobile communication; Computational modeling; Concatenated codes; Demodulation; Error correction codes; Fading; Iterative decoding; Maximum likelihood decoding; Mobile communication; Wireless communication;

fLanguage

English

Publisher

ieee

Conference_Titel

Vehicular Technology Conference, 2000. IEEE-VTS Fall VTC 2000. 52nd

Conference_Location

Boston, MA

ISSN

1090-3038

Print_ISBN

0-7803-6507-0

Type

conf

DOI

10.1109/VETECF.2000.886668

Filename

886668