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.
We present a density-based clustering method producing a covering of the dataset by ellipsoidal structures in order to detect possibly entangled clusters. We first introduce an unconstrained version of the algorithm which does not require any assumption on the number of clusters. Then a constrained version using a priori knowledge to improve the bare clustering is discussed. We evaluate the performance...
Quaternion-valued adaptive filters based on the mean square error (MSE) criterion have been extensively studied in recent years. However, the MSE cost function has only one degree of freedom, and to circumvent this problem, we propose another criterion which enables separate control of the magnitude and phase. Next, a quaternion least mean magnitude phase (QLMMP) filtering algorithm is introduced...
The limited availability and the lack of continuity in the service of Global Positioning Satellite Systems (GNSS) in harsh environments is a critical issue for Intelligent Transport Systems (ITS) applications relying on the position. This work is developed within the framework of vehicle-to-everything (V2X) communication, with the aim to guarantee a continuous position availability to all the agents...
Phase noise compensation plays an indispensable role in realizing the potential of orthogonal frequency division multiplexing (OFDM) for high-data-rate communications. Due to various heuristics employed to deal with the particular properties of phase noise, the existing approaches are still performance-limited in terms of accuracy and computational cost. In this paper, we focus on channel estimation...
Time delay estimation in multipath environments is important for many applications in the fields of radar, sonar, communication and so on. In this paper, we propose a method based on compressed sensing for time delay estimation. In the proposed method, the signal in time domain is first converted into frequency domain, which tends to convert the problem to a parameter estimation of sinusoidal signals...
Inverse Synthetic Aperture Radar (ISAR) can obtain images of targets with high resolution under the condition of all-time, all-weather and long-distance, thus ISAR is of great value in both military and civil application areas. In order to improve the resolution of the images, super-resolution imaging algorithms have broken through the Rayleigh limit and have been widely employed in ISAR imaging....
Based on ESPRIT algorithm and integer search method, a two — dimensional DOA estimation algorithm is proposed for the LFM signal under sub-Nyquist sampling. A non-uniform L-type antenna array model is established, ESPRIT algorithm and integer search method are used to get the original signal azimuth and pitch angle information accurately. This algorithm can reduce the computational complexity effectively...
In this paper, we propose the use of multiple Gaussian kernels for distributed nonlinear regression or system identification tasks by a network of nodes. By employing multiple kernels in the estimation process we increase the degree of freedom and thus, the ability to reconstruct nonlinear functions. For this, we extend the so-called KDiCE algorithm, which allows a distributed regression of nonlinear...
We propose a novel joint tracking and mitigation scheme for linear dynamic impairments using a 3-stage extended Kalman filter. Simulation results show that it can quickly track and compensate the impairments including multi-polarization effects, frequency offset and phase noise.
Algorithms for estimating the symbol rate of signals with modulation types M-PSK and M-FSK are presented. The algorithm for estimating the symbol rate of the M-PSK signals is based on the Fourier transform of the squares of the modules of the complex envelope of the signal. The algorithm for estimating the symbol rate of M-FSK signals is based on the separation of the spectrum of the original signal...
This paper presents a modified rank-reduction (RARE) method for joint direction-of-arrival (DOA) estimation and gain-phase calibration with some partly calibrated uniform linear arrays. Through recursively building up RARE matrices, the proposed method can guarantee the estimated gain-phase coefficients being unique, so as to improve the stability of gain-phase calibration performance. Another advantage...
This paper presents a compressed sensing based sensor selection algorithm for direction-of-arrival estimation, in a large scale randomly distributed sensor array. First, a target tracker is employed for the prior information of target position. Second, according to the prior information, we reduce rank of sensing matrix by narrowing the interesting area. Third, a linear independence combination of...
Quadrature downconversion impairments should be taken into account and compensated to the increasing of the Direct Conversion Receiver (DCR) reception quality. DC-offset and I/Q-imbalance are fitted into this group. Experimental estimation of two relatively simple compensation methods for the indicated drawbacks is reviewed in the paper. Energy efficiency and computational complexity estimation are...
the use of digital multifunction protection relays and their proper integration on power system and smart grid is an important element. However, the performance of digital relays depends on many factors and needs to be carefully evaluated. These factors may be caused correct operations with less performance or completely incorrect operations. Frequency deviation is one of those factors which results...
Estimation of periodic quantities such as angles or phase values is a common problem. However, standard approaches, for example the Kalman filter and extensions thereof, have difficulties when estimating periodic quantities. To address this problem, circular filtering algorithms have been proposed but they are limited to just a single angle. In order to deal with multiple, possibly correlated angles,...
In this paper, we propose the bias-compensated distributed diffusion LMS algorithm to estimate the parameter in the presence of multiplicative regressor noise to mitigate the estimation bias caused by multiplicative regressor noise. In the case where the multiplicative regressor noise exists, the estimate produced by standard distributed diffusion LMS algorithm will be biased. To validate the algorithm,...
In order to solve the coherent problem of Orthogonally Matched(OMP) Pursuit algorithm in sparse reconstruction, the feature vector corresponding to large eigenvalue of SVD is constructed by using received data, and two improved methods are proposed. Both methods reconstruct the angle through the feature vector, and can reconstruct the angle information accurately without knowing the number of the...
The problem of two-dimensional (2D) direction of arrival (DOA) estimation with non-uniform L-shaped array is discussed. The generalized ESPRIT algorithm (GESPRIT) has an advantage of being suitable to arbitrary array geometry. However, the direct applying of (GESPRIT) algorithm in non-uniform L-shaped array (called 2D-GESPRIT) needs an exhaustive 2D spectral search, which makes it unfeasible in practice...
In military communication and several direction finding applications, precise estimation of the DOA, incorporated with smart beam-forming techniques, can provide useful solutions for interference mitigation and jammer identification. Compressive Sensing (CS) based DOA approaches offer a competitive advantage over the traditional DOA estimation techniques due to their ability to obtain an estimate...
A coprime array enables an increased number of degrees-of-freedom by deriving a non-uniform virtual array. However, existing work such as spatial smoothing fails to utilize all of the information provided by the coprime array, which results in performance loss. In this paper, we propose a novel coprime virtual array interpolation-based direction- of-arrival (DOA) estimation algorithm by Toeplitz matrix...
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.