Performance Study of a Near Maximum Likelihood Code-Aided Timing Recovery Technique

Abstract : In this paper, we propose a new code-aided (CA) timing recovery algorithm for various linear constant modulus constellations based on the Maximum Likelihood (ML) estimator. The first contribution is the derivation of a soft estimator expression of the transmitted symbol instead of its true or hard estimated value which is fed into the timing error detector (TED) equation. The proposed expression includes the Log-Likelihood Ratios (LLRs) obtained from a turbo decoder. Our results show that the proposed CA approach achieves almost as good results as the data-aided (DA) approach over a large interval of SNR values while achieving a higher spectral efficiency. We also derive the corresponding CA Cramer Rao Bounds (CRB) for various modulation orders. Contrarily to former work, we develop here the CRB analytical expression for different M-PSK modulation orders and validate them through comparison to empirical CRB obtained by Monte Carlo iterations. The proposed CA estimator realizes an important gain over the non data-aided approach (NDA) and achieves a smaller gap when compared to its relative CA CRB, especially at moderate SNR values where modern systems are constrained to work.
Type de document :
Article dans une revue
IEEE Transactions on Signal Processing, Institute of Electrical and Electronics Engineers, 2016, 〈10.1109/TSP.2015.2489602〉
Liste complète des métadonnées

Littérature citée [35 références]  Voir  Masquer  Télécharger

https://hal-ensta.archives-ouvertes.fr/hal-01248388
Contributeur : Benoit Geller <>
Soumis le : vendredi 25 décembre 2015 - 21:58:18
Dernière modification le : lundi 12 février 2018 - 15:42:11
Document(s) archivé(s) le : samedi 26 mars 2016 - 10:40:48

Fichier

27article_ieee_trans.pdf
Fichiers produits par l'(les) auteur(s)

Identifiants

Citation

Imen Nasr, Benoit Geller, Leila Najjar Atallah, Sofiane Cherif. Performance Study of a Near Maximum Likelihood Code-Aided Timing Recovery Technique. IEEE Transactions on Signal Processing, Institute of Electrical and Electronics Engineers, 2016, 〈10.1109/TSP.2015.2489602〉. 〈hal-01248388〉

Partager

Métriques

Consultations de la notice

144

Téléchargements de fichiers

171