Trellis-based soft-output adaptive equalization techniques for TDMA cellular systems

Author

Park, Jong, II ; Wicker, Stephen B. ; Owen, H.L.

Author_Institution

Dept. of Electr. Eng., Koean Mil. Acad., Seoul, South Korea

Volume

49

Issue

1

fYear

2000

fDate

1/1/2000 12:00:00 AM

Firstpage

83

Lastpage

94

Abstract

The concatenation of an equalizer and a Viterbi (1967) decoder is a powerful means for improving receiver performance in wireless communication systems. A soft-output equalizer increases the impact of this combination by enabling the use of soft-decision Viterbi decoding. It is well known that the maximum a posteriori (MAP) algorithm provides optimal reliability information, but at the cost of substantial complexity. This paper contains the results of an investigation into the design and performance of soft-output adaptive equalization techniques based on suboptimum trellis-based soft-output decoding algorithms. It is shown that the performance improvement relative to hard output equalizers is substantial, while the cost in terms of complexity is modest. A time-division multiple-access (TDMA) cellular system is used as the basis for comparisons. Simulation results and a complexity analysis are presented

Keywords

Viterbi decoding; adaptive equalisers; cellular radio; digital radio; multipath channels; multiuser channels; radio receivers; time division multiple access; time-varying channels; MAP algorithm; TDMA cellular systems; Viterbi decoder; adaptive equalizer; complexity analysis; decoding algorithms; digital mobile radio channels; maximum a posteriori algorithm; optimal reliability information; performance; receiver performance; simulation results; soft-decision Viterbi decoding; soft-output equalizer; suboptimum trellis-based soft-output decoding; time-division multiple-access; time-varying multipath propagation; trellis-based soft-output adaptive equalization; wireless communication systems; Adaptive equalizers; Algorithm design and analysis; Analytical models; Channel coding; Decoding; Land mobile radio; Military computing; Time division multiple access; Viterbi algorithm; Wireless communication;

fLanguage

English

Journal_Title

Vehicular Technology, IEEE Transactions on

Publisher

ieee

ISSN

0018-9545

Type

jour

DOI

10.1109/25.820701

Filename

820701