Igor Djurovie, Vesna Popović–Bugarin, Marko Simeunović,
A two-stage technique for estimating micro-Doppler signal parameters has been proposed. In the first stage, rough parameter estimations are performed by regression of instantaneous frequency estimate obtained from the short-time Fourier transform. Afterwards, rough estimates are refined in the second stage. The proposed technique has better performance with respect to current state-of-the-art algorithms, and it reaches the Cramer–Rao lower bound for sinusoidal frequency-modulated signal parameters.
Tópico(s): Ultrasonics and Acoustic Wave Propagation
2017 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Aerospace and Electronic Systems
Igor Djurović, Marko Simeunović,
Several papers have been published recently on the quasi-maximum likelihood (QML) approach for the polynomial phase signals (PPS) parameter estimation. The QML is powerful alternative to phase differentiation (PD) based techniques. It achieves the Cramer–Rao lower bound (CRLB) for low SNR values even for high-order PPS. The QML is generalized for signals with non-polynomial modulation and can work for impulsive noise environment. Since it is based on the linear time–frequency (TF) representation, short- ...
Tópico(s): Structural Health Monitoring Techniques
2017 - Elsevier BV | Digital Signal Processing
Igor Djurović, Marko Simeunović, Pu Wang,
Tópico(s): Underwater Acoustics Research
2017 - Elsevier BV | Signal Processing
Igor Djurović, Marko Simeunović,
The quasimaximum likelihood (QML) estimator of polynomial-phase signals (PPSs) is based on the maximization of the short-time Fourier transform and suffers from aliasing when signals are sampled below the Nyquist sampling rate. In this paper, a phase unwrapping procedure has been proposed as an additional step in the QML to estimate parameters of such signals. Statistical study has shown excellent performance of the proposed approach.
Tópico(s): Machine Fault Diagnosis Techniques
2016 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Aerospace and Electronic Systems
Marko Simeunović, Igor Djurović,
This paper considers parameter estimation of multicomponent 2D polynomial-phase signals (mc-2D PPSs). The main contributions included are: Derivation of the Cramer-Rao lower bound (CRLB) for mc-2D PPSs; Two dimensional product high-order ambiguity function (2D PHAF) based estimation procedure, recently proposed by Barbarossa, for the estimation of third-order mc-2D PPSs is extended to signals of arbitrary orders; Procedure for optimal lag set selection in the proposed 2D PHAF has been proposed; Since ...
Tópico(s): Underwater Acoustics Research
2015 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Signal Processing
Marko Simeunović, Igor Djurović,
Parameter estimation of polynomial phase signals (PPSs) based on the cubic phase function (CPF) and its extensions cannot be performed by using the fast Fourier transform (FT) algorithm. Therefore, in order to express the CPF by means of the FT, in this paper we propose a scheme for the CPF evaluation based on non-uniform sampling. Calculation complexity of the estimation procedure is significantly reduced, whereas the accuracy is the same or better compared to the original algorithm.
Tópico(s): Machine Fault Diagnosis Techniques
2014 - Elsevier BV | Signal Processing
Ljubiša Stanković, Igor Djurović, Srdjan Stanković, Marko Simeunović, Slobodan Djukanović, Miloš Daković,
The instantaneous frequency (IF) is a very important feature of nonstationary signals in numerous applications. The first overview of the concept and application of the IF estimators is presented in seminal papers by Boashash. Since then, a significant knowledge has been gained about the performance of the IF estimators. This knowledge has been used not only for development of various IF estimators but also for introduction of novel time–frequency (TF) representations. The IF estimation in environments ...
Tópico(s): Speech and Audio Processing
2014 - Elsevier BV | Digital Signal Processing
Igor Djurović, Slobodan Djukanović, Marko Simeunović, Predrag Raković, B. Barkat,
Abstract We consider the joint estimation of the direction-of-arrival (DOA) and parameters of wideband polynomial-phase signals (PPSs) in sensor array. Unlike concurrent methods that require multidimensional searches, the proposed method requires 1D searches for all the parameters of interest. In this way, we can efficiently estimate the considered parameters in applications where large antenna arrays, containing tens or hundreds of sensors, are used. As special cases, we consider in detail the estimation ...
Tópico(s): Advanced Adaptive Filtering Techniques
2012 - Springer Science+Business Media | EURASIP Journal on Advances in Signal Processing
Igor Djurović, Marko Simeunović, Slobodan Djukanović, Pu Wang,
In this paper, we consider parameter estimation of high-order polynomial-phase signals (PPSs). We propose an approach that combines the cubic phase function (CPF) and the high-order ambiguity function (HAF), and is referred to as the hybrid CPF-HAF method. In the proposed method, the phase differentiation is first applied on the observed PPS to produce a cubic phase signal, whose parameters are, in turn, estimated by the CPF. The performance analysis, carried out in the paper, considers up to the tenth- ...
Tópico(s): Structural Health Monitoring Techniques
2012 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Signal Processing
Igor Djurović, Marko Simeunović, Budimir Lutovac,
The estimation of polynomial-phase signals (PPSs) is a multiparameter problem, and the maximum likelihood (ML) optimization functions have numerous local optima, making the application of gradient techniques impossible. The common solution to this problem is based on the phase differentiation (PD) techniques that reduce the number of dimensions but, at the same time, reduce the accuracy and generate additional difficulties such as spurious components and error propagation. Here we show that genetic ...
Tópico(s): Direction-of-Arrival Estimation Techniques
2012 - Elsevier BV | Digital Signal Processing
Marko Simeunović, Igor Djurović,
A simple and effective modification of the high-order ambiguity function (HAF) is introduced. The number of phase differentiations is decreased to two with respect to the HAF. The obtained signal has a cubic phase, the parameters of which can be estimated using the cubic phase function (CPF) in the final stage. The SNR threshold of the proposed modification is reduced for 9 dB with respect to the HAF, while the MSE is about 2 dB less.
Tópico(s): Machine Fault Diagnosis Techniques
2011 - Institution of Engineering and Technology | Electronics Letters
Igor Djurović, Cornel Ioana, T. Thayaparan, Ljubiša Stanković, P. Wang, Vesna Popović–Bugarin, Marko Simeunović,
A cubic-phase function evaluation technique for multicomponent frequency-modulated signals with non-overlapped components in the time–frequency (TF) plane is proposed. The proposed technique is based on the short-time Fourier transform. Cross-terms are removed or reduced in the same manner as in the case of the TF representation called the S-method. The proposed technique is applied for visualisation of signals in time-chirp-rate plane and parameter estimation of analytical and radar signals. In ...
Tópico(s): Structural Health Monitoring Techniques
2010 - Institution of Engineering and Technology | IET Signal Processing
Igor Djurović, Marko Simeunović,
Tópico(s): NMR spectroscopy and applications
2013 - Springer Science+Business Media | Signal Image and Video Processing
Predrag Raković, Marko Simeunović, Igor Djurović,
This paper considers joint estimation of the direction-of-arrival (DOA) and coefficients of polynomial-phase signal (PPS) that impinge an uniform linear sensor array (ULA). Recently introduced method referred to as the polynomial beamformer (PB) being the maximum likelihood estimator for these parameters suffers from high computational complexity due to a multidimensional search. Hence, its applicability is limited only to the second-order PPSs while it is unfeasible for higher-order PPSs as it is heavily ...
Tópico(s): Advanced Adaptive Filtering Techniques
2016 - Elsevier BV | Signal Processing
Igor Djurović, Ljubiša Stanković, Marko Simeunović,
An efficient procedure for obtaining time–frequency representations under high influence of impulsive noise is proposed in this paper. The procedure uses the fast Fourier transform based algorithm instead of sorting procedures common in the case of various robust time–frequency representations proposed recently. Concentration measure is used to select a free parameter of the transform.
Tópico(s): Spectroscopy and Chemometric Analyses
2014 - Elsevier BV | Signal Processing
Igor Djurović, Marko Simeunović,
Parameter estimation of non-uniformly sampled polynomial-phase signals (PPSs) is addressed in this paper. It is assumed that signals are sampled below the rate required by the sampling theorem. The recent advance in the field, based on combining the high-order cubic phase function (HO-CPF) and high-order Wigner distribution (HO-WD), has been applied for parameter estimation of such signals. Two cases of the sampling scheme are considered: (i) random sampling with symmetrically distributed samples around ...
Tópico(s): Image and Signal Denoising Methods
2014 - Elsevier BV | Signal Processing
Igor Djurović, Pu Wang, Marko Simeunović, Philip V. Orlik,
This paper considers parameter estimation of a new coupled mixture of polynomial phase signal (PPS) and sinusoidal frequency modulated (FM) signal, recently introduced for industrial systems such as linear electromagnatic encoders. Compared with both conventional PPS-only and independent mixture models, the coupled mixture one captures the coupling between the sinusoidal FM frequency and the PPS parameters induced by structural system configurations. In this paper, we are particularly interested in ...
Tópico(s): Structural Health Monitoring Techniques
2018 - Elsevier BV | Signal Processing
Nevena Radović, Veselin N. Ivanović, Igor Djurović, Marko Simeunović, Ervin Sejdić,
Tópico(s): Power Quality and Harmonics
2022 - Birkhäuser | Circuits Systems and Signal Processing
Igor Djurović, Vladimir Lukin, Marko Simeunović, B. Barkat,
Several papers in the literature cover parameter estimation of frequency modulated (FM) signals under reduced number of signal samples with respect to the Nyquist/Shannon criterion, i.e., within the compressive sensing (CS) framework. However, scope of these papers is mainly limited to sinusoids or sum of sinusoids. In this paper, the CS framework is extended to parameter estimation of higher order polynomial phase signals (PPSs) using the quasi-maximum likelihood (QML) estimator and robust short-time ...
Tópico(s): Image and Signal Denoising Methods
2014 - Elsevier BV | AEU - International Journal of Electronics and Communications
Marko Simeunović, Igor Djurović, Slobodan Djukanović,
This paper considers refinement in parameter estimation of 2-D polynomial phase signals (PPSs). For this purpose, a method based on phase unwrapping, filtering and polynomial fitting is developed. In the method, 2-D parameter estimation is reduced to 1-D refinement procedure, thus significantly gaining in calculation efficiency. As initial estimates, the proposed method takes the estimates provided by any 2-D parameter estimator. In this paper, we use initial estimates provided by the standard Francos– ...
Tópico(s): Advanced Electrical Measurement Techniques
2013 - Elsevier BV | Signal Processing
Nevena R. Brnović, Igor Djurović, Veselin N. Ivanović, Marko Simeunović,
Flexible, multiple-clock-cycle, hardware design for the quasi-maximum likelihood (QML) algorithm core realisation for the polynomial phase signals (PPSs) estimation is proposed. The QML algorithm significantly outperforms existing PPS estimators in terms of accuracy. However, its practical applications require efficient software and hardware systems. The main challenges in the proposed hardware development with respect to existing systems for time–frequency (TF) analysis are realisation of TF representation ...
Tópico(s): Advanced Electrical Measurement Techniques
2018 - Institution of Engineering and Technology | IET Circuits Devices & Systems
Kruna Ratković, Nataša Kovač, Marko Simeunović,
Air pollution is a critical environmental concern that poses significant health risks and affects multiple aspects of human life. ML algorithms provide promising results for air pollution prediction. In the existing scientific literature, Long Short-Term Memory (LSTM) predictive models, as well as their combination with other statistical and machine learning approaches, have been utilized for air pollution prediction. However, these combined algorithms may not always provide suitable results due ...
Tópico(s): Vehicle emissions and performance
2023 - Multidisciplinary Digital Publishing Institute | Applied Sciences
Igor Djurović, Marko Simeunović,
The two-dimensional (2D) cubic phase function (CPF) is known as a highly accurate 2D polynomial phase signal estimator, but it has limited applicability due to the requirement for the 3D search for second-order partial phase derivatives. The authors propose an interpolation-based approach simulating non-uniform (NU) signal sampling in order to reduce the 2D CPF calculation complexity. The NU resampling enables the 2D CPF evaluation using the 2D fast Fourier transform and searches over mixed-phase parameter. ...
Tópico(s): Geophysical Methods and Applications
2018 - Institution of Engineering and Technology | IET Signal Processing
Marko Simeunović, Igor Djurović,
Parameter estimation of polynomial phase signals is usually performed by maximizing the cost function. To reduce the calculation complexity, the maximization consists of coarse and fine estimation stages. To refine coarse estimate, in this paper, we propose a method based on filtering and phase unwrapping of transform function. Simulation experiments have shown excellent results compared to classical fine estimation algorithms such as Aboutanios–Mulgrew and dichotomous search.
Tópico(s): Machine Fault Diagnosis Techniques
2018 - Elsevier BV | Digital Signal Processing
Ruslan Kozhemiakin, Vladimir Lukin, Sergey Abramov, Marko Simeunović, B. Djurovic, Igor Djurović,
We propose and study an approach to compression ratio prediction and providing with application to multichannel remote sensing images. DCT-based compression techniques, both 2D applied component-wise and 3D applied to sub-band groups, are considered. It is shown that compression ratio can be predicted for component-wise processing of multichannel images using a simple modification of approach proposed recently for coding single-component images, either noise-free or corrupted by different types ...
Tópico(s): Advanced Data Compression Techniques
2016 - Begell House | Telecommunications and Radio Engineering
Slavko Rakić, Nenad Simeunović, Nenad Medić, Marko Pavlović, Uglješa Marjanović,
The use of service in the manufacturing sector is growing in the last decade. Moreover, there are developed and implemented many service business models across the world. Prior studies investigated the role of service business models in the manufacturing sector of developed countries; however, the role of service business models in transition economies (e.g., Serbia) is neglected. This research provides an overview of the use of service business models in the manufacturing sector of the Republic ...
Tópico(s): Quality and Supply Management
2020 - Springer Science+Business Media | IFIP advances in information and communication technology
Marko Simeunović, Kruna Ratković, Nataša Kovač, Tamara Racković, António Fernandes,
Tópico(s): Wine Industry and Tourism
2025 - Multidisciplinary Digital Publishing Institute | Sustainability
António Fernandes, Nataša Kovač, Hélder Fraga, André Fonseca, Sanja Radonjić, Marko Simeunović, Kruna Ratković, Christoph Menz, Sergi Costafreda-Aumedes, João A. Santos,
The Montenegrin climate is characterised as very heterogeneous due to its complex topography. The viticultural heritage, dating back to before the Roman empire, is settled in a Mediterranean climate region, located south of the capital Podgorica, where climate conditions favour red wine production. However, an overall increase in warmer and drier periods affects traditional viticulture. The present study aims to discuss climate change impacts on Montenegrin viticulture. Bioclimatic indices, ensembled ...
Tópico(s): Plant and animal studies
2024 - Multidisciplinary Digital Publishing Institute | ISPRS International Journal of Geo-Information
Igor Djurović, Marko Simeunović,
Parametric estimation of polynomial phase signals (PPSs) corrupted by an impulsive noise has been considered. The interpolation in joint-variable domain has been combined with the hybrid cubic phase function-high-order ambiguity function-based estimator to address this issue. Technique for estimating the percentage of impulses and threshold selection is also proposed. In addition, we propose the refinement procedure to further decrease the mean squared error of PPS parameters estimates.
Tópico(s): Blind Source Separation Techniques
2018 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Aerospace and Electronic Systems
Marko Simeunović, Igor Djurović, Alen Pelinković,
Tópico(s): Direction-of-Arrival Estimation Techniques
2018 - Springer Science+Business Media | Multidimensional Systems and Signal Processing