Frederik Simoens

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In recent years, it has been recognized that bit-interleaved coded modulation with iterative decoding (BICM-ID) achieves excellent performance on virtually any channel, provided the signal mapping is carefully designed. In this paper, we introduce multidimensional mapping for BICM-ID, where a group of bits is mapped to a vector of symbols, rather than a(More)
This paper investigates linear precoding for bit-interleaved coded modulation (BICM) on additive white Gaussian noise (AWGN) channels. Concatenating a linear precoder as an inner encoder with an outer (convolutional) encoder produces a powerful code with a limited decoding complexity. Linear precoders are examined and optimized for two scenarios: using (i)(More)
This paper concerns channel tracking in a multiantenna context for correlated flat-fading channels obeying a Gauss-Markov model. It is known that data-aided tracking of fast-fading channels requires a lot of pilot symbols in order to achieve sufficient accuracy, and hence decreases the spectral efficiency. To overcome this problem, we design a code-aided(More)
The paper deals with carrier frequency offset estimation for a flat-fading multiple-input multiple-output (MIMO) channel using a training sequence. The resulting maximum likelihood (ML) estimation entails solving a maximization problem with no closed-form solution. Since numerical calculation of the estimate is computationally hard, we propose a sub-optimal(More)
In this paper, we consider linear precoders for Bit-Interleaved Coded Modulation with iterative decoding (BICM-ID) on AWGN channels. In a BICM-ID set-up, the encoder and symbol mapper are separated by an interleaver in order to achieve better performance and to allow a simplified (yet sub-optimal) decoding strategy. However, careful design of the symbol(More)
In this contribution, we present a novel multiple-input multiple-output (MIMO) detection scheme for quadrature amplitude modulation (QAM). The proposed method is based on the slowest descent (SD) method and is suitable for both iterative and non-iterative detectors. Optimal MIMO detection entails maximizing or marginalizing a likelihood function over a very(More)
This contribution deals with carrier frequency offset estimation for flat-fading multiple-input multiple-output (MIMO) channels. Both data-aided (using training symbols) and iterative code-aided (using the unknown coded symbols) estimation is considered. In both scenarios, maximum-likelihood (ML) frequency offset estimation involves solving a maximization(More)
This paper deals with joint data detection, synchronization and channel parameter estimation for direct-sequence code-division multiple-access systems over frequency-selective channels. In low-signal-to-noise ratio environments, conventional data-aided (DA) estimation algorithms may require an unacceptably large number of pilot symbols in order to obtain(More)
This paper investigates the use of Monte Carlo sampling methods for phase noise estimation on additive white Gaussian noise (AWGN) channels. The main contributions of the paper are (i) the development of a Monte Carlo framework for phase noise estimation, with special attention to sequential importance sampling and Rao-Blackwellization, (ii) the(More)