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Classifying leukocyte and examining their proportions is a very important for disease examination and diagnosis. This examination needs the knowledge of experts and a lot of time. Therefore, many automatic leukocyte images classification algorithms have been proposed. There is a method to classify 13 types blood cells using One versus One Support Vector Machine in one of them. In the conventional...
In this paper, a short review of radar cross-section (RCS) profiles of typical metallic shapes of targets is addressed. The aim is to show that the intensity of forward-scattering usually prevails over backward-scattering, especially at higher frequencies. It is also shown that a large geometrical aspect ratio of typical obstacles leads to more omnidirectional scattering in one of the scattering planes...
This article presents the first results of river ice cover observation with Sentinel-1 data for the Vistula river (Poland). To our best knowledge this is the first study when Sentinel-1 data have been used to monitor ice cover changes during the whole season of ice phenomena. Frequent data acquisition allowed to detect changes every 3–5 days. We used an algorithm based on the log likelihood change...
A concept of advanced navigation radar for purposes of hydrographie sea surface surveillance with fine azimuth resolution is considered. The advancement of radar system supposes modification of non-coherent pulse radar to operate in coherent mode, and to design additional receiver module to obtain radar data with improved azimuth resolution. The description and simulated characteristics of proposed...
Creating two-dimensional ISAR images is a well-known technique used as a basis for radar non-cooperative target recognition (NCTR). This paper investigates the impact of the lack of rotational motion compensation on the stability of ISAR image formation using sparse signal reconstruction. Series of simulations were conducted, using the Orthogonal Matching Pursuit (OMP) algorithm for scene reconstruction,...
We present nonlinear Schur-type orthogonal representations of nonlinear filters of the Volterra-Wiener class for higher-order and non-Gaussian stochastic processes, and propose efficient and numerically attractive solutions of the orthogonal transformations (innovations, stochastic modeling) for this class of processes.
Augmented reality is popular and rapidly growing direction. It is successfully used in medicine, education, engineering and entertainment. In the paper, basic principles of typical augmented reality system are described. An efficient hybrid visual tracking algorithm is proposed. The approach is based on combining of the optical flow technique with direct tracking methods. It is demonstrated that developed...
Nowadays, as indoor localization systems are gaining their popularity, simple installation and deployment become more important. The paper deals with the problem of anchor nodes position estimation. In most cases, to be able to calculate the tag's positions it is necessary to know the exact positions of the elements of the system's infrastructure. The method for anchor nodes' position estimation based...
The paper presents digital image objects detection and recognition system using artificial neural networks and drones. It contains description based on example of person identification system where face is the key object of processing. It describes the structure of the system and components of the learning sub-system as well as the processing sub-system (detection, recognition). It consists of a description...
The feasibility of asteroid detection using the Forward Scatter Radar Network that exploits three pulsars as transmitters is examined. We provide a power budget estimate for asteroid detection using such a FSR-network with the radio telescope used as a receiver. The numerical results are obtained for two known radio telescopes in the Netherland and three known pulsars.
The results of analyses devoted to the improvement of parameters of pipeline analog-to-digital converters (ADCs) using a new method for computing output codes are presented and discussed. The proposed method is based on two main modifications of principles of conventional pipeline ADCs operation. Firstly, it assumes that the values of the gains of inter-stage amplifiers can be set to the arbitrary...
Passive radars are emerging technologies that use non-cooperative transmitters instead of dedicated ones. They present a set of advantages with respect to active ones, such as lower cost and low probability of intercept, but require complex signal processing stages due to the use of non-controlled transmitters. IDEPAR demonstrator is a DVB-T based passive radar developed by the University of Alcalá...
The paper presents the way of operation of a Vision-Based Navigation (VBN) system based on the Scene Matching Area Correlation (SMAC) algorithm and demonstrates its applicability for highly autonomous navigation of Unmanned Aerial Vehicles (UAVs). Chosen simulation results included in the paper show that the algorithm proposed by the authors works properly in ideal conditions and demonstrate its acceptable...
The paper describes Noise waveform reflectometer of a new type, which uses wideband random signals and spectral interferometry method for fiber optical network diagnostics. Also correlation based reflectometer was submitted and investigated. These reflectometers have no so-called “dead zone” and are used for metrological support of fiber-optic communication lines (FOCL).
Ste gano graphic systems are used for the transmission of hidden data in the original signal. The article describes the algorithm of the hidden data transmission using the speech signal as a carrier. The echo method is used for data embedding. In order to improve the decoding efficiency of embedded data, the procedure of voicing correction and mechanism of informed coding were developed and implemented...
This paper tackles the study of the nondesired effects in the detection capabilities and system resolution of Passive Radar (PR) solutions due to sporadic interference. Real radar data acquired by IDEPAR demonstrator (DVB-T based PR system developed by the University of Alcala) with the presence of an interference were considered. The ambiguity function is calculated to estimate the pedestal mean...
In this paper, we present nonlinear estimators of nonstationary and multicomponent signal attributes (parameters, properties) which are instantaneous frequency, spectral (or group) delay, and chirp-rate (also known as instantaneous frequency slope). We estimate all of these distributions in the time-frequency domain using both finite and infinite impulse response (FIR and IIR) narrow band filers for...
Cognitive radio (CR) is an effective way to improve the utilization of spectrum resource. This paper focuses on the resource allocation in cooperative relay cognitive radio networks and proposes an optimized resource allocation algorithm. In the algorithm, when the channel between the primary source and destination is good, the primary user (PU) selects a best sub-channel to transmit its data directly,...
Most of real-life signals are nonGaussian, therefore the linear parametrization/modeling methods, suitable for Gaussian signals are neither adequate nor optimal. Using a nonlinear approach, we can significantly improve filtering results. However, the price that has to be paid is the complexity of the nonlinear treatment. In this paper we consider the nonlinear Schurtype orthogonal transformations...
Recently more attention has been paid to the space debris orbiting the Earth. Until 5 July 2016, the United States Strategic Command tracked a total of 17 729 artificial objects including 1419 operational satellites[1]. Information about the current position of these objects should be taken into consideration while planning space missions. There are various solutions to cope with the problem considered...
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