Bidirectional Viterbi decoding algorithm for OvTDM

Overlapped time domain multiplexing (OvTDM) is an innovative encoding scheme that can obtain high spectral efficiency. However, the intentional inter-symbol interference (ISI) caused by OvTDM will make the decoding process more complex. The computational complexity of maximum likelihood sequence det...

Full description

Saved in:
Bibliographic Details
Published in:China communications Vol. 17; no. 7; pp. 183 - 192
Main Authors: Wang, Haocheng, Wang, Yafeng, Hu, Yue
Format: Journal Article
Language:English
Published: China Institute of Communications 01.07.2020
Key Laboratory of Universal Wireless Communication, Ministry of Education, Beijing University of Posts and Telecommunications, Beijing 100876, China
Subjects:
bidirectional Viterbi algorithm (BVA)
Convolutional codes
decoding performance
Encoding
Maximum likelihood decoding
Multiplexing
overlapped time domain multiplexing (OvTDM)
Spectral efficiency
Viterbi algorithm
Viterbi algorithm (VA)
Viterbi algorithm (VA)
overlapped time domain multi-plexing (OvTDM)
decoding performance
bi-directional Viterbi algorithm (BVA)
ISSN:1673-5447
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Overlapped time domain multiplexing (OvTDM) is an innovative encoding scheme that can obtain high spectral efficiency. However, the intentional inter-symbol interference (ISI) caused by OvTDM will make the decoding process more complex. The computational complexity of maximum likelihood sequence detection increases exponentially with the growth of spectral efficiency in OvTDM. As a consequence of high complexity, the decoding effort for a given spectral efficiency may occasionally exceed the physical limitations of the decoder, leading inevitably to buffer overflows and information erasures. In this paper, we propose a bidirectional Viterbi algorithm (BVA) based on the bidirectional sequence decoding for OvTDM. With the BVA, the decoding operation starts simultaneously from the both ends of the corresponding trellis and stops at the middle of trellis. The simulation results show that compared with Viterbi algorithm (VA), the decoding time of BVA can be reduced by about half. And the memory space of two decoders in BVA are about half of that in VA, which means that the BVA has lower memory requirements for decoder. And the decoding performance of BVA is almost the same as VA.
ISSN:1673-5447
DOI:10.23919/J.CC.2020.07.013