Performance analysis of dual-hop fixed-gain AF relaying systems with OSTBC over Nakagami-m fading channels

Serife Seda Kucur
Elsevier Gmbh, Urban & Fischer Verlag, 2012
Article

In this paper, we present outage probability and symbol error rate (SER) performance analyses of a dual-hop transmission using fixed-gain amplify-and-forward relaying in flat Nakagami-m fading channels. The system under consideration is equipped with multiple antennas at source and destination adopting orthogonal space-time block coding to provide transmit diversity and maximum ratio combining to provide receive diversity, respectively. For integer and half-integer m values, closed forms of exact outage probability and moment generating function (MGF) expressions are derived through cumulative distribution function (CDF) of the overall system signal-to-noise ratio. Closed-form exact SER expressions based on the overall CDF are obtained for binary phase shift keying, binary frequency shift keying and M-ary pulse amplitude modulation. Exact SER expressions based on the MGF method are also obtained for binary differential phase shift keying, M-ary phase shift keying and M-ary quadrature amplitude modulation. Moreover, the asymptotic diversity order analysis is performed through derivations of asymptotic outage probability and SER. Theoretical analyses are validated by Monte Carlo simulations showing perfect match between each other. (C) 2012 Elsevier GmbH. All rights reserved.

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Concepts associés

Chargement

Publications associées

Chargement

Serife Seda Kucur
Elsevier Gmbh, Urban & Fischer Verlag, 2012
Article

Résumé

Official source

https://infoscience.epfl.ch/record/184698?ln=fr

À propos de ce résultat

Concepts associés (14)

Concepts associés

Chargement

Publications associées (1)

Publications associées

Chargement

Adaptive "load-distributed" muscle coordination method for kinematically redundant musculoskeletal humanoid systems

Nadia Barbara Figueroa Fernandez

Muscle force control of musculoskeletal humanoid systems has been studied for years in the motor control, biomechanics and robotics disciplines. However, the study of "load-distributed" muscle control has seldomly been contemplated. In this paper, we consider muscle force control as a problem of muscle coordination. We propose a general muscle coordination method for a system driven by agonist and antagonist muscles. In our method, a set of linear equations is derived by connecting the acceleration description in both joint and muscle space where the pseudo inverse solution to these equations provides an initial optimal muscle force distribution. Thereafter, we redistribute the forces throughout the muscles by deriving a gradient direction for muscle force. This allows the muscles to satisfy force constraints and generate a distribution of forces throughout all the muscles. Moreover, to ensure that our proposed method is adaptive to modeling errors, we have constructed an estimated system model, which is added to the system to represent the real plant. By updating the parameters of the estimated model based on prediction error, the estimated model approaches the real plant gradually in real-time. The overall proposed method is evaluated on a bending-stretching movement of a musculoskeletal arm. We used two models (arm with 6 and 10 muscles) to verify the method. The force distribution analysis verifies the "load-distribution" property of the computed muscle force. The efficiency comparison shows that the computational time does not increase significantly with the increase of muscle number. The tracking error statistics of the two models show the validity of the method. (C) 2014 Elsevier B.V. All rights reserved.

Elsevier Science Bv2015

Chargement

Système

Un système est un ensemble d' interagissant entre eux selon certains principes ou règles. Par exemple une molécule, le système solaire, une ruche, une société humaine, un parti, une armée etc. Un s

Fonction de répartition

En théorie des probabilités, la fonction de répartition, ou fonction de distribution cumulative, d'une variable aléatoire réelle X est la fonction F{{sub|{{mvar|X}}}} qui, à

Rapidité de modulation

Dans un canal de communication utilisant une méthode de transmission par éléments temporels discrets, dont les canaux de communication numériques, la rapidité de modulation, aussi appelée « vitesse d