Conference Paper

# On the analysis of the MAP equalizer performance within an iterative receiver

ISECS, Sfax, Tunisia

DOI: 10.1109/SPAWC.2004.1439281 Conference: Signal Processing Advances in Wireless Communications, 2004 IEEE 5th Workshop on Source: IEEE Xplore

- [Show abstract] [Hide abstract]

**ABSTRACT:**To combat the effects of intersymbol interference, the optimal equalizer to be used is based on maximum a posteriori (MAP) detection. We consider the case where the MAP equalizer is provided with a priori information on the transmitted data, as in a turbo equalizer. We propose to study analytically the impact of the a priori on the MAP equalizer performance. We distinguish two cases: the case of unreliable a priori and the case of reliable a priori. In a turbo equalizer, the equalizer and the decoder exchange extrinsic Log Likelihood Ratios (LLRs). We propose here to study analytically their distribution. The aim of this study is to perform in the future the analytical convergence analysis of turbo equalizers using the MAP equalization. -
##### Article: Impact de l'a priori sur les performances de l'égaliseur MAP et distribution des LRV extrinsèques

[Show abstract] [Hide abstract]

**ABSTRACT:**Afin de combattre les effets des interférences entre symboles (IES), l'égaliseur optimal à utiliser est basé sur le critère Maximum a posteriori (MAP). Nous considérons le cas où l'égaliseur MAP est alimenté par des informations apriori sur les données émises, comme pour un turbo égaliseur. Nous proposons d'étudier analytiquement l'impact de l'a priori sur les performances de l'égaliseur MAP. Nous distinguons deux cas d'étude : le cas où les informations a priori sont fiables et le cas où elles ne sont pas fiables. Dans un turbo égaliseur, l'égaliseur et le décodeur s'échangent des Logarithmes du Rapport de Vraisemblance (LRV) extrinsèques pour améliorer les performances au fil des itérations. Nous proposons ici d'étudier analytiquement la distribution de ces LRV. Le but de cette étude est d'effectuer de manière analytique, dans un travail futur, l'analyse de la convergence des turbo égaliseurs utilisant un égaliseur MAP.20° Colloque sur le traitement du signal et des images, 2005 ; p. 595-598. -
##### Conference Paper: Performance analysis of the MAP equalizer with a priori and distribution of the extrinsic LLRs

[Show abstract] [Hide abstract]

**ABSTRACT:**To combat the effects of intersymbol interference, the optimal equalizer to be used is based on maximum a posteriori (MAP) detection. We consider the case where the MAP equalizer is provided with a priori information on the transmitted data, as in a turbo equalizer. We propose to study analytically the impact of the a priori on the MAP equalizer performance. We distinguish two cases: the case of unreliable a priori and the case of reliable a priori. We show that when the a priori is reliable, it is better to perform the detection of the transmitted symbols based on the a posteriori outputs of the MAP equalizer rather than on the a priori only. In a turbo equalizer, the equalizer and the decoder exchange extrinsic log likelihood ratios (LLRs). We propose here to study analytically their distribution. The aim of this study is to perform in the future the analytical convergence analysis of turbo equalizers using the MAP equalization.Signal Processing Advances in Wireless Communications, 2005 IEEE 6th Workshop on; 07/2005

Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.