Frieder Sanzi

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—In this letter, we investigate two iterative channel estimators for mobile orthogonal-frequency division multi-plexing. The first estimator is based on iterative filtering and decoding whereas the second one uses an a posteriori probability (APP) algorithm. The first method consists of two cascaded one-dimensional Wiener filters, which interpolate the(More)
—In this paper an adaptive channel estimator is proposed and investigated to improve the performance of the receiver for pilot aided wireless and mobile OFDM systems. The estimator consists of a two-dimensional Wiener filter which is implemented as a cascade of two one-dimensional filters. We propose an efficient algorithm for adaptation to time varying(More)
— In this paper, we extend the iterative demapping technique, also known as turbo demodulation, to OFDM. We first introduce an inner code which serves to remove the error floor, which is present in current iterative demapping schemes. This technique is then applied to OFDM with cyclic prefix or zero-padding. Using the EXIT chart, we illustrate the(More)
This publication has been included here just to facilitate downloads to those people asking for personal use copies. This material may be published at copyrighted journals or conference proceedings, so personal use of the download is required. In particular, publications from IEEE have to be downloaded according to the following IEEE note: c 2007 IEEE.(More)
— In this paper we consider a Multi Carrier Code Division Multiplex (MC–CDM) scheme. At the receiver side the Maximum A Pos-teriori Symbol–by–Symbol Estimator (MAPSSE) is used for the detection of the CDM signal. Therefore the influence of the spreading factor on the overall Bit Error Rate (BER) is investigated. We concatenate the MAPSSE with the channel(More)
—A new two-dimensional blind channel estimation scheme for coherent detection of orthogonal frequency-division multiplexing (OFDM) signals in a mobile environment is presented. The channel estimation is based on the a posteriori probability (APP) calculation algorithm. The time-variant channel transfer function is completely recovered without phase(More)
— A new two-dimensional blind channel estimation scheme for coherent detection of OFDM signals in a mobile environment is presented. The channel estimation is based on the A Posteriori Probability (APP) calculation algorithm. The time-variant channel transfer function is completely recovered without phase ambiguity with no need for any pilot or reference(More)
Totally blind APP channel estimation is based on the A Posteriori Probability (APP) calculation algorithm. Asymmetrical modulation schemes are used in order to resolve the phase ambiguity with no need for any pilot or reference symbols. In OFDM-systems, the two-dimensional channel estimation is performed by applying a concatenation of two one-dimensional(More)