Valery Ramon

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—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)
—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 non-diagonal matrix, even in the frequency domain. In order to regain the(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-maxi-mization (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)
Spatial Multiplexing (SM) is an effective means for enhancing the transmission data rate in Multiple-Input Multiple-Output (MIMO) systems, particularly when used in combination with precoding. Precoding based on the knowledge of the slow-varying statistics of the channel exploits this information at the transmitter to combat the effect of fading in SM(More)
The current paper addresses the issue of estimating the users 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-max-imization (EM) algorithm and takes benefit from the soft information(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)