Mohamed Lassaad Ammari

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Algebraic Space-Time Codes (ASTC) for MIMO systems are based on quaternion algebras. Thanks to their algebraic construction, the ASTC codes are full-rank, full-rate and have the non-vanishing determinant property. These codes have been proposed for MIMO flat fading channels in order to increase the spectral efficiency and to maximize the coding gain. The(More)
In this paper, we consider the detection of turbo coded symbols in orthogonal frequency division multiplexed (OFDM) systems and propose a turbo detector composed of a turbo decoder and a channel estimator. These modules perform jointly and exchange a soft information through an iterative process. The decoder consists of the maximum a posteriori MAP-BCJR(More)
In this paper we suggest to use the ASTC (Algebraic Space Time Codes) as powerful coding technique for IEEE 802.11x OFDM standard combined with PAPR reduction scheme. ASTC with their very Algebraicconstruction based on Quaternionic algebra, have a full rate, full diversity, non-vanishing constant minimum determinant for increasing spectral efficiency,(More)
BACKGROUND It has been suggested that disturbed activity of the autonomic nervous system is one of the factors involved in gastroesophageal reflux (GER) in adults. We sought to establish whether transient ANS dysfunction (as assessed by heart rate variability) is associated with the occurrence of GER events in neonates during sleep and wakefulness. (More)
This work deals with the detection of turbo-coded symbols in orthogonal frequency-division multiplexed (OFDM) systems. OFDM symbol detection requires channel estimation, which is often carried out using known pilots. In this paper, an iterative detector composed of a turbo decoder and a channel estimator is proposed. These modules perform jointly and(More)
In this paper, we analyze the performance of an Algebraic Space Time Codes (ASTC), called the Golden code. Due to its Algebraic construction based on Quaternionic algebra, the code has a full rate, full diversity, non-vanishing constant minimum determinant for increasing spectral efficiency, uniform average transmitted energy per antenna and good shaping.(More)
This paper presents a new algebraic carrier frequency offset (CFO) estimation technique for multiple-input-multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) system, to overcome the sensitivity of algebraic space-time codes (ASTCs) to frequency synchronization in quasi-static correlated Rayleigh frequency-selective fading channels. The(More)
This letter studies the performance of the line-of-sight underground mine channel in the millimeter-wave band. Using a vector network analyzer (VNA) and three carefully chosen antennas, one omni and two horn antennas, we performed measurements at the 40- and 70-m levels in the CANMET mine located in Val-d'Or, QC, Canada. The performance of the channel is(More)
In this work we provide a methodology for the design and verification of a frequency domain equalizer. The performance analysis of the equalizer is conducted using two methods: simulation based verification in Simulink and System Generator and theorem proving techniques in Higher Order Logic. We conduct both floating-point and fixed-point error estimations(More)