Research

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Wireless Communications

Our research interests are in the area of wireless communications, including optical wireless.

We are working on statistical characterization of fading and interference in different receiver configurations, and on diversity reception as one of the fading mitigation strategies.

Channel characterization for free-space optical communications, including statistical random media models describing turbulence effects is part of our research work.

To some extent, there is an analogy between the fading and interference effects in radio communication systems and turbulence effects in optical wireless systems, so some of the mitigation procedures are similar, and therefore many of the results can be shared between the two technologies.

Quantization and Signal Compression

Our focus is on development of algorithms for high/medium quality compression and coding of speech and audio signals.

More specifically, our researchers deal with design and performance evaluation of different models for discretization and coding of continuous signals. Quantizer and source coder modules are part of communication system and their optimization directly affects the overall performance and the quality of service (QoS). 

Development of nonlinear parametric models for speech prediction, particularly models based on truncated Volterra series, and improvement of the long–term pitch prediction in analysis–by–synthesis coders are part of our research. 

These results can be applied in PSTN and VoIP networks; audio, image and video coding, speech coding; general A/D converter design; acoustic echo cancellation and speaker recognition.

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Signal Processing and Sound Design

This research field is related to spatial components of sound recording and reproduction. It includes analysis of spatial aspects of the sound field using specific transducers, typically surrounded microphone array or compact spherical microphone array. 

Development of the method for design of 1D and 2D linear phase digital FIR filters by applying different variants of Christoffel-Darboux formula for orthogonal (orthonormal) polynomials. The filters designed in this way are highly selective, and all parasitic effects are suppressed. 

The application covers various areas including telecommunications, acoustics and audio, microwave technique, etc. different topics are covered including effects of sound transmission through human ear, coupling of earphones to human ear and artificial coupler, effects of equipment calibration to the results of hearing tests, development of new methods for hearing tests. 

We explore development of system identification technique based on numerical solution of fractional (non-integer) order differential equations and orthogonal distance fitting which is applicable for arbitrary number of spatial dimensions. 

Our researchers work on time and frequency domain analysis of the linear fractional-order systems. Possible applications are in modeling of multidimensional dynamical systems and signal processing.

Artificial Intelligence (AI)

Our team works on AI tasks that include speech and pattern recognition, digital signal processing, and decision-making solutions in healthcare, energy sector, manufacturing, cyber security, etc.

Due to its multidisciplinary aspect and fast advancements in machine and deep learning, many companies are interested in building smart solutions in order to stay competitive and survive on today’s market. 

Our partners on AI research come from academia and industry

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Decision-making

Decision-making deals with making judgments and decisions, especially in situations that involve risk and uncertainty. Decision-making provides us with knowledge on good and poor outcomes of individuals and organizations, and how we can use this knowledge to make better informed decisions. 

Decision-making is applied in politics, marketing, medicine, health, etc. 

Our experts closely collaborate with different companies and publish their research in academic journals and books, as well as presenting at major national and international conferences.