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  • Thomas Kaiser, André Bourdoux, Holger Boche, Javier Rodríguez Fonollosa, Jørgen Bach Andersen, Wolfgang Utschick +34 others
  • 2005
Preface It was in the summer of 2002 when the European Union launched the Sixth Framework Research Programme. One of the expected outcomes of this multibillion Euro initiative was Structuring, that is, tackling the fragmentation of European research on a large scale. The concept of the so-called Network of Excellence (NoE) was born, which was designed to(More)
  • Heidi Steendam, Marc Be, Moeneclaey, Marc Moeneclaey@telin Ugent Be
  • 2007
In this paper, we consider different types of guard intervals for OFDM systems, i.e. cyclic prefix (CP), zero padding (ZP) and known symbol padding (KSP). We compare the different OFDM systems with respect to their SNR performance. We show that CP-OFDM and ZP-OFDM have exactly the same performance, whereas KSP-OFDM has a slightly worse performance. Further,(More)
In this contribution we consider the Cramer-Rao bound (CRB) for the estimation of the time delay of a noisy linearly modulated signal with random data symbols and random carrier phase. Because of the presence of the nuisance parameters (i.e., data symbols and carrier phase), a closed-form expression of this CRB is very hard to obtain for arbitrary PSK, QAM(More)
—This paper is devoted to turbo synchronization, that is to say the use of soft information to estimate parameters like carrier phase, frequency offset or timing within a turbo receiver. It is shown how maximum-likelihood estimation of those synchronization parameters can be implemented by means of the iterative expectation-maximization (EM) algorithm [1].(More)
This contribution considers turbo synchronization, that is to say, the use of soft data information to estimate parameters like carrier phase, frequency, or timing offsets of a modulated signal within an iterative data demodulator. In turbo synchronization, the receiver exploits the soft decisions computed at each turbo decoding iteration to provide a(More)
—In OFDM systems, the symbol timing synchronization is needed to find an estimate of where the symbol starts. The most popular of the pilot-aided timing estimators is the one proposed action of the timing estimator may be strongly affected by the presence of disturbances, like narrowband interference (NBI) signals. This paper investigates the effect of NBI(More)
In this paper, we give an overview of the sensitivity of a number of multicarrier systems to carrier and clock synchronization errors. A comparison is made between orthogonal frequency division multiplexing/multiple access (OFDM(A)) and two combinations of the orthogonal multicarrier technique and the code-division multiple access (CDMA) technique, i.e.,(More)
—This contribution deals with two hypothesis testing problems for digital receivers: frame synchronization and phase ambiguity resolution. As current receivers use powerful error-correcting codes and operate at low signal-to-noise ratio (SNR), these problems have become increasingly challenging: one is forced either to waste a part of the bandwidth on(More)
We investigate the sensitivity to carrier phase jitter of an orthogonal frequency-division multiple access (OFDMA) system. When all OFDMA carriers have the same power level and the jitter spectrum, the degradation caused by the jitter is shown to be equal to the degradation of an OFDM system. Also, traditional FDMA is found to be slightly more robust than(More)
— In this paper, we consider the effect of a carrier phase offset on the performance of a low-density parity-check (LDPC) coded QAM modulated system. We investigate an ML-based carrier phase synchronization algorithm, that makes use of the posterior probabilities of the data symbols, provided by the iterative decoder. The resulting carrier phase(More)