The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This work focuses on adaptive Broadband Radio Access Network (BRAN) channel identification and on downlink Multi-Carrier Code Division Multiple Access (MCCDMA) equalization. We use the normalized BRAN C channel model for 4G mobile communications, distinguishing between indoor and outdoor scenarios. On the one hand, BRAN C channel parameters are identified using the Least Mean p-Power (LMP) algorithm...
The resolution of a Direction of Arrival (DOA) estimation algorithm is determined based on its capability to resolve two closely spaced signals. In this paper, authors present and discuss the minimum number of array elements needed for the resolution of nearby sources in several DOA estimation methods. In the real world, the informative signals are corrupted by Additive White Gaussian Noise (AWGN)...
In this paper, the blind equalization problem in presence of bounded noise with different modulations (QAM, PSK and ASK) is addressed. A first blind equalization algorithm is reminded, then an extension is proposed. Few synthesis parameters have to be fixed by the user in the proposed approach. In order to illustrate the efficiency of the proposed algorithm, we compare with another well known existing...
In this paper, we provide two algorithms for blind equalization in a bounded noise environment of a Single Input Single Output (SISO) channel. These approaches are based an Optimal Bounding Ellipsoid (OBE) algorithms. This class is among the set Membership identification methods. The aim of these algorithms is to force the equalizer output constellation to match the input constellation by estimating...
This document surveys the blind equalization issue. Our approach is based on the reformulation of the equalization problem in an identification problem in existence of limited noise. The objective of the proposed method is to estimate the settings of the equalizer such that the output of the equalizer is in a neighborhood of the input constellation. The proposed method can be applied in real-time...
In this paper, the localization of wideband source with an algorithm to track a moving source is investigated. To locate the wideband source, the estimation of two directions of arrival (DOA) of this source from two different arrays of sensors is used, and then, a recursive algorithm is applied to predict the moving source’s position. The DOA is estimated by coherent subspace methods, which use the...
The purpose of this paper is the passive angular location of the wideband sources using an array of sensors. The improvement of the two-sided correlation transformation (TCT) is proposed, only the signal subspace estimated at each frequency is transformed by focusing matrices such that to obtain the coherent signal sub-space for all the analysis band. The simulation results show that the proposed...
This paper presents a propagator method for high resolution estimation of the angles of arrival of multiple wideband plane waves without eigendecomposition. The technique is based on a partition of the array spectral matrix. The noisy situation is considered and an algorithm to eliminate the noise contribution is given. The results of simulations support the theoretical predictions are presented.
In this paper, we present a subspace-based method for direction finding for radiolocation of localization of mobile station. Indeed, an original partition of the data cross-spectral matrix is proposed in order to use a small part of the observations to estimate the noise subspace projector without eigendecomposition, when the number of sensors of antennas is very larger than the number of sources...
In this paper, different techniques for the estimation of the signal parameters and/or the channel coefficients for single-input/multiple-output systems, arc presented. These methods arc based, cither on the use of a small part of observations or on the minimization of a quadratic form with quadratic constraint. Simulations have been established and these techniques arc compared to the classical approaches.
Source localization problem consists of an ensemble of techniques that are used to obtain spatial information of present radiation in given medium of propagation, with a constraint of the antenna geometry and the characteristics of radiating sources. This condition gives multitude of cases to study, hence several methods were proposed in the literature. In this paper, a new algorithm for estimating...
In this paper, we present an algorithm for blind equalization i.e. equalization without training sequence. The proposed algorithm is based on the reformulation of the equalization problem in a set membership identification problem. Among the Set Membership Identification methods, the chosen algorithm is an optimal bounding ellipsoid type algorithm. This algorithm has a low computational burden which...
In this paper a comparative study, restricted to one-dimensional stationary case, between several Direction of Arrival (DOA) estimation algorithms of narrowband signals is presented. The informative signals are corrupted by an Additive White Gaussian Noise (AWGN), to show the performance of each method by applying directly the algorithms without pre-processing techniques such as forward-backward averaging...
In this paper, a comparative study between a blind algorithm, based on higher order cumulants, and adaptive algorithms, i.e. Recursive Least Squares (RLS) and Least Mean Squares (LMS) for MultiCarrier Code Division Multiple Access (MC-CDMA) systems equalization is presented. Two practical frequency-selective fading channels, called Broadband Radio Access Network (BRAN A, BRAN B) normalized for MC-CDMA...
In this paper, we consider the problem of selective radio channel identification. Two technics are used, the first one is based on Higher Order Statistics (HOS), the second is based on Takagui-Sugeno (TS) fuzzy systems. In order to evaluate the proposed algorithms, we have used two practical selective frequency fading channels called Broadband Radio Access Network (BRAN A and BRAN E) normalized for...
This paper describes two blind algorithms for multicarrier code division multiple access (MC-CDMA) system equalization. In order to identify, blindly, the impulse response of two practical selective frequency fading channels called broadband radio access network (BRAN A and BRAN E) normalized for MC-CDMA systems, we have used higher order cumulants (HOC) to build our algorithms. For that, we have...
In this paper, we propose a method for the localisation of wideband sources in order to locate mobile station. Indeed, directions-of-arrival of wideband sources are estimated by coherent subspace methods, which use the focusing operators, in the presence of a correlated noise and, then, the angulation is used to determine the mobile's position. Practical methods of the estimation of the coherent signal...
In this contribution, we consider the problem of blind identification of Finite Impulse Response (FIR) system driven by a stochastic chaotic signal. Because of the inherently deterministic nature of a chaotic signal, we initialize the recursive equation which define the chaotic signal, by a random number, this leads to a random excitation. It was observed that the equalization performance of the chaotic...
In this work an observer is proposed for the state estimation of each node in a communication network composed of cascade active queue. The queue length of each node in the network must be estimated by the use of our proposed observer. This observer is based in the fluid flow dynamical model for an active link of communication between two hosts trough the network. We show that this model is include...
A scheme of chaotic spreading sequence for multicarrier code division multiple access system (MC-CDMA) iproposed to estimate the transmission channel. This systespreads spectrum and identifies the channel, simultaneously. The proposed scheme uses a chaotic sequence generated by a logistic map as a training signal and estimate channel parameters according to dynamics of the chaotic sequence. Encoding...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.