Valery Ramon

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The current paper addresses the issue of estimating the sampling instant in turbo receivers. The proposed synchronizer is based on the expectation-maximization (EM) algorithm and takes benefit from the soft information delivered by the turbo system. Performance Interpolator Anti−aliasing Turbo Demodulator Matched filter a posteriori information Discrete(More)
This paper deals with maximum-likelihood (ML) estimation of synchronization parameters for coded transmission systems. In particular, we present a unified framework based on both the sum-product (SP) algorithm and the expectation-maximization (EM) algorithm for the design of iterative synchronizers. The proposed approach is shown to encompass some known(More)
This paper proposes a simple semi-analytical method with reduced simulation time for predicting at any iteration the performance of a turbo-equalization/demapping scheme using the Wang and Poor soft-in/soft-out (SISO) minimum mean-square error (MMSE)/interference cancellation (IC) equalizer and a SISO decoder. The proposed method may be applied to(More)
In this paper, we develop a new low-complexity linear frequency domain equalization (FDE) approach for continuous phase modulated (CPM) signals. As a CPM signal is highly correlated, calculating a linear minimum mean square error (MMSE) channel equalizer requires the inversion of a nondiagonal matrix, even in the frequency domain. In order to regain the FDE(More)
We present a new symbol block construction which yields a cyclic continuous phase modulated (CPM) signal to enable frequency domain equalization. It is known that in addition to a cyclic prefix, a subblock of data-dependent symbols has to be inserted in each block to cope with the memory in the CPM signal. We propose a new subblock, called intrafix, valid(More)
This paper places turbo synchronization into the sum-product (SP) and the expectation-maximization (EM) algorithm framework. In particular, we show that the combination of these algorithms enables to design low-complexity and very powerful synchronisers. The proposed synchronizer is compared to a previously-proposed EM framework. As the derivation suggests,(More)
The current paper addresses the issue of estimating the user propagation delays, received carrier phase offsets and received amplitudes in an asynchronous DS-CDMA environment with frequency non-selective propagation channels. The proposed synchronizer is based on the expectation-maximization (EM) algorithm and takes benefit from the soft information(More)
The large bandwidth available at 60 GHz together with the resulting wavelength of only 5 mm allow the design of multi-gigabit/s wireless devices equipped with large arrays of tiny antennas. This enables wireless communication of large contents multimedia such as high-definition video. However, due to the high cost and power consumption of analog frond-end(More)
One of the techniques for spectrum sensing is the energy detection of signals from primary transmitters. However, when detecting in a certain frequency band, this technique suffers from the random fading introduced by the channel. This problem can be alleviated by the use of multiple antennas introducing spatial diversity. The performance of the energy(More)