Skip to Main content Skip to Navigation

Techniques de surcharge en utilisateurs d’un canal à accès multiple

Abstract : This thesis is dedicated to the channel overloading concept, which refers to the situation in which a system accommodates a greater number of users than allowed by the use of orthogonal signal waveforms. We showed the existence of two families of construction at the transmitter side allowing a spectral efficiency gain by the increase of the number of users. The first family of techniques includes the schemes making use of combinations of orthogonal CDMA and possibly of TDMA, and a construction proposed in the literature by Ross and Taylor. We investigated and compared the performance given by different methods of multiuser detection based on an iterative interference cancellation principle, which can be applied to these schemes in the absence of coding, on a Gaussian channel or on a non-selective Rayleigh fading channel. We next considered schemes from the second family of construction: on the one hand a scheme proposed following the interpretation of the above mentioned schemes as multilevel coding, and on the other hand IDMA (Interleave-Division Multiple Access), whose performance was studied on a Gaussian channel without coding, and compared to the other channel overloading techniques. Finally, we presented through a general matrix formalism some iterative techniques adapted to schemes with channel coding, and which can be used on a Gaussian or a Rayleigh multipath channel. Thus, several receiver structures adapted to each scheme (CDMA or IDMA) were proposed.
Document type :
Complete list of metadata

Cited literature [133 references]  Display  Hide  Download
Contributor : Florence Nadal Connect in order to contact the contributor
Submitted on : Friday, April 13, 2018 - 10:50:31 AM
Last modification on : Monday, December 14, 2020 - 12:29:06 PM


Files produced by the author(s)


  • HAL Id : tel-01765868, version 1



Florence Nadal. Techniques de surcharge en utilisateurs d’un canal à accès multiple. Traitement du signal et de l'image [eess.SP]. SUPELEC, 2006. Français. ⟨tel-01765868⟩



Record views


Files downloads