Issued topics of Doctoral Study Program:|
- Active Devices in Advanced Classes for Telecommunication Applications
The aim of the project is in the solutions of amplifiers or multipliers in advanced classes E, F, G and other in the microwave band. These classes allow improving various parameters of standard circuits, such as efficiency, intermodulation level and others, depending on specific application. The change of parameters is done with the use of manipulation of harmonic frequencies of input signal. Work will focus also on output circuit design to realize necessary harmonic manipulation. In the work it will be necessary to simulate those circuits, to realize selected designs and select proper methodology of measurements in the case of designed circuits.
- Advanced EMI Filters Models
The project is focused on the analysis of single-phase EMI filters. The analysis has to be focused on the uncertain impedance termination of the EMI filters. The termination has a dominant influence on the filter's insertion loss and also on so call "worst-case" performance. The results will be checked by a lot of measurements and also several mathematical analyses. For these analyses will be designed accurate filter's models.
- Advanced microwave systems for space communication
At present, there are new interesting MIO based on GaN, discrete devices and new materials which allow to find solutions of microwave parts of the ground as well as the space segments on new principles. These are namely antenna feeds with integrated low noise amplifiers, power amplifiers, quadrature frequency converters, local oscillators with low phase noise, frequency filters, frequency synthesizers, modulators and demodulators. A part of the project will be studies of application possibilities, parameters analysis and designs of extensional units of a satellite communication chain.
- Advanced ultrasound sensors for distance measurements
The goal of this project is to find new methods for improving ultrasound sensors for distance measurement used in automotive industry. Current trend is an extension of the measurable distance (both minimum distance and maximum distance), a possibility to use a coding and a concurrent measurement using several sensors (each sensor is equipped with a different code and a distinction of received reflected signal is done based on a detection of the received code), adaptive methods of measurement of parameters of used ultrasound sensors and optimization of the system based on actual parameters of the sensor and advanced diagnostic methods.
Expert advisor: doc. Dr. Ing. Pavel Horský, ON Design Czech
- Analysis and modeling of the transmission in the third generation digital television ATSC 3.0
Third generation of Advanced Television Systems Committee (ATSC 3.0) standard introduces advanced technical solutions (e.g. LDM multiplexing, communication technology MIMO) and very flexible system parameters (e.g. higher order QAM modulation). This dissertation thesis focuses on the exploring and basic analysis of signal transmission in terrestrial digital television standard ATSC 3.0. A prerequisite of the successful analysis is a creation of an appropriate simulation model, allows to simulate and analyze the signal transmission, considering multipath transmission and selective fading, with adjustable system parameters of the transmitter and receiver system blocks. A possible verification of theoretical (simulation) results by an experimental laboratory measurement (e.g. SDR-USRP) is also considered. The main aim of this work is the definition of the influence of the system parameters on the bit error rate (BER) and on the quality of the signal transmission.
- Analysis and simulation of the transmission in the second generation digital television using spatial diversity technique
The next generation of terrestrial digital video broadcasting standard (DVB-T2) incorporates the option of using multiple-input single-output (MISO) spatial diversity transmission technique. This dissertation thesis focuses on the exploring and analysis of signal transmission in the second generation terrestrial digital television standard (DVB-T2/T2-Lite) uses spatial diversity transmission techniques MISO and in the future MIMO. A prerequisite of such analysis is a creation of an appropriate simulation model, allows to simulate and analyse the signal transmission which consider multipath propagation with selective fading, and adjustable system parameters of the transmitter and receiver system blocks. A possible verification of theoretical (simulation) results by measurement either in a real environment or in laboratory conditions is also considered. The main aim of this work is the definition of the influence of the system parameters on the bit error rate (BER) and on the quality of the signal transmission.
- Analysis of nonlinear electronic systems using Volterra series theory
The aim of the project is to elaborate ways of description of nonlinear electronic systems using Volterra series theory and find effective methods of their solution. In theoretical part, existing methods will critically be evaluated and computationally more efficient procedures searched, including multivariate Laplace transform approach and related numerical techniques. Attention will be focused on use in the analysis of systems with distributed parameters with nonlinearities. In experimental part, dependencies between Volterra series kernels and X-parameters measured by nonlinear vector network analyzer are supposed to be exploited. Potential candidates should have an interest in applied mathematics and programming in MATLAB.
- Analysis of stochastic changes of interconnects parameters
The aim of the project is to develop techniques of the analysis of stochastic changes of interconnects parameters in electronic systems on a basis of the theory of stochastic differential equations (SDE). The subject of the research will be devoted partly to the application of ordinary SDEs, useful to describe models with lumped parameters, and partly to the study of the applicability of partial SDEs, useful for continuous models based on the telegraphic equations. It is expected generalization of some proposed techniques towards the analysis of hybrid electronic systems based on stochastic differential-algebraic equations (SDAE). Effectiveness of the proposed methods will be evaluated by comparison with standard statistical approaches such as Monte Carlo method. Potential candidates should have an interest in applied mathematics and programming in MATLAB.
- Applications of electronically controllable bilinear two-ports for approximation of functional blocks with fractional order character
This work deals with synthesis/approximation of network building blocks (integrator, derivator, etc.) of the fractional order circuit by help of chains of subparts employing bilinear transfer sections of the integer order where independent electronic control of the zero and pole location is allowed. This approximation (valid in limited frequency bandwidth) allows to obtain fractional exponent of the Laplace operator s and construction of the so-called “half integrator” (1/s^0.5) for example. The work in this topic is focused to circuit theory but partial results will be verified experimentally with attention to suitable practical applications and applications in smart components of physical layer of communication systems.
- Coexistence between wireless communication networks and digital broadcasting networks in shared frequency bands
This dissertation thesis focuses on the definition and exploring of possible coexistence scenarios between wireless communication services (e.g. LTE/LTE-A, IEEE 802.22, IEEE 802.11af/ah) and digital video broadcasting services (DVB-T/T2/T2-Lite). Such coexistence scenarios can be critical (a partial or full loss of services, provided by considered communication systems), and non-critical (both communication systems can coexist without significant performance degradation). The aim of this work is to verify defined coexistence scenarios and their analysis with appropriate simulation models. Verification of theoretical (simulation) results by measurement either in a real environment or in laboratory conditions is also considered. Based on the results, recommendations for a coexistence-free operation of wireless communication systems in shared frequency bands will be defined.
- Coexistence of wireless communication systems in shared ISM frequency bands
The fifth-generation (5G) technology is the next step in the evolution of advanced wireless communication systems, where wireless equipment can process radio frequency signals, provided by various communication systems in a shared frequency band. This dissertation thesis focuses on the definition and exploring of possible coexistence scenarios between advanced wireless communication standards (e.g. LTE/LTE-A and IEEE 802.11g/n/ac) in shared ISM frequency bands. These scenarios can be critical (a partial or full loss of services, provided by considered communication systems), and non-critical (both communication systems can coexist without significant performance degradation). The aim of this work is to verify defined coexistence scenarios and their analysis with appropriate simulation models. Verification of theoretical (simulation) results by measurement either in a real environment or in laboratory conditions is also considered. Based on the results, recommendations for a coexistence-free operation of wireless communication services in shared frequency bands will be defined.
- Detection of alcohol by voice analysis
Proposed project is oriented to detection of alcohol using signal analysis of phone speech. The aim of this project is development and testing of special algorithms for investigation of alcohol intoxication in low level which is not audible but affect the activity and behaviour of persons. Development of algorithms will be based on robust DSP methods applicable both in real-time analysis and stored signal analysis. In addition, some specific databases under realistic conditions will be created.
- Determination of the limits of the quantitative parameters in optical wireless communication
The work is focused on the study of atmospheric turbulence, which is an important factor affecting the properties of optical radiation. The work consists of detailed analysis of the turbulent media and describes horizontal and vertical models of the atmosphere. The methodology for quantification of the degree of turbulence considering the needs of optical wireless communication is the next point of the work.
- Determination of the optical beam parameters of the full photonics transmitter
The aim of this project is to develop, justify and verify the method designed for measuring of the coherence and polarization of the optical beams that are intended for communication in conditions of turbulent atmosphere. The design of the laser transmitter working with several beams which form a “top hat” beam as a result is a part of the project. It will be necessary to create a program using the method of Fourier Optics for the optical beams simulation, their composition and their propagation in the turbulent atmosphere. The experimental verification of mutual interference of the beams is requested.
- Distributed receiving system for satellite communication
The project is aimed at study of synchronized distributed SDR receivers performance and at their application for satellite communication. The proposed system should allow simultaneous reception and data extraction from multiple signals. The main target of the study is enhancement of error-free data reception probability, exploitation of distributed system gain and stations redundancy. System is determined for data reception from experimental satellites in UHF band.
- Electronically controllable oscillators of higher and fractional orders
Research is focused on modeling, simulations and experimental verification of circuit realizations of higher-order harmonic oscillators and inharmonic generators for structures of physical layer of communication systems working in base and inter-frequency band. The main task is to found features and application possibilities of circuits with higher order than 3 and circuits defined by differential equations of fractional order. An attention will be concentrated on frequency tunability, phase and magnitude relations between generated signals and suitable amplitude stabilization especially. Part of the work deals with detailed description of signal generation based on linear and nonlinear mathematical operations that are allowed by implementation of so-called constant phase elements producing constant phase shift between excitation signal and response.
- Channel models for future generations of mobile networks
Steadily growing number of communication devices per area and increasing quality of services require allocation of more frequency resources. Millimeter wave (MMW) frequencies between 30 and 300 GHz have been attracting growing attention as a possible candidate for next-generation broadband cellular networks. Specific limitations of MMW signal propagation, extremely large bandwidth and time variable environment caused by mobile users connected to a backhaul networks traveling in rugged municipal environments create unprecedented challenges to the development of broadband communication systems using advanced technologies for eliminating the undesirable time varying channel features. The aim of the project is measurement and modelling of the broadband non-stationary MMW channels in time and spatial domain (i.e. modelling the environment between mobile users and backhaul) in order to evaluate feasibility of advanced techniques such as beamforming or massive MIMO spatial multiplexing implementation.
- Increase of fault coverage on methods for testing analog circuits
The project is focused on the improvement of methods for testing analog circuits including RF. It is possible, by means of suitably chosen test points, to identify a circuit component that is faulty of its value is out of specifications. The theoretical part of the project includes research into methods for the optimum choice of test points and research into methods for identification of the faulty element with the help of symbolic analysis. The work may include practical design of software for verification of designed methods. Prospective applicant should be interested in analog circuits and computer simulation methods.
- Inteligent feeding networks
The aim of the project is area of passive and active circuits, which allow changes to signal transmission in the position of feeding network, for example phasing circuits, tunable filter circuits etc. Proposed structure should be modeled theoretically and verified by realization targeted on perspective bands of centimeter and millimeter waves. Application of the circuits should be targeted to intelligent antenna systems, which will allow reconfigurablility during operation. Project target is mainly in the complex reconfigurability in the multi dimensions.
- Learning deep architectures
Deep architectures are composed of multiple levels of non-linear operations (e.g., artificial neural networks with hidden layers). Searching the parameter space of deep architectures is a difficult task, but learning algorithms have been recently proposed to tackle this problem.
The project is focused on a detailed study of deep architectures and their learning, on their software implementation using parallel computing, and their applications in field of computational electromagnetics.
- Low-profile directional antennas for band of millimeter waves
The project is focused on the research of the novel low-profile antenna concepts for the band of millimeter waves. The attention of the project should be concentrated on the development of novel technologies and exploitation of novel materials for antenna design. Further attention should be focused on circuits connected to an antenna. Proposed antenna concepts should find application in directional radio links for selected frequency bands.
- Methods for precise positioning in wireless sensor networks
The subject of this project is focused on research of methods and hardware systems for precise localization of wireless sensors in networks. The goal of the research is analysis of current methods and their optimization with application in millimeter bands (MMID), eventually sub-millimeter bands, using UWB signals. Topic of the project includes an effective cooperation of multi-sensor systems (proper protocols, Kalman filtering). Systems for precise positioning of robotic machines, personal localization in buildings, in-car detection of a driver, or accurate localization of RFID tags are objective applications of this research.
- Methods of multiple access and beamforming for future mobile networks
Ever increasing demands for high-speed transmission in mobile networks lead to the use of increasingly higher frequency bands. In the area of millimeter wave band there is a sufficient bandwidth but extremely growing path loss. The short wavelengths, however, allow to realize tiny antennas and combine them into arrays offering a large gain, that are able significantly eliminate the path loss.
The project is aimed at the research and development of algorithms for adaptive beamforming in combination with massive MIMO that would be able to combine optimally both approaches depending on the channel state and user requirements. The project includes study of a possible hardware implementation of the proposed algorithms and methods of antenna arrays control.
- Model of a shared transmission channel for future wireless communication systems
Doctoral thesis is focused on analysis of the modern and future wireless communication systems and their coexistence in a shared transmission channel. During the analysis, the systems like digital television broadcasting (eg. DVB-T/T2, NGH), standards for mobile communications (eg. GSM/UMTS/LTE), wireless communication systems (eg. ZigBee, BT, WLAN, WPAN) etc., have to be taken into account. Prerequisite of the successful solution is definition of the statistical model of the transmission channel with variable parameters and then its verification including simulated coexistence with various wireless services. The aim of the work is not only the model of the transmission channel, but also a definition of the forward error correction scheme that is optimized for the verified and shared transmission channel model.
- Modeling of Pulsed Plasmonic Antenna Structures
The thesis aims at the space-time electromagnetic analysis of antenna systems showing plasmonic properties. The research will focus in particular on the analytic description of pulsed radiation characteristics of selected antenna structures with emphasis on their distortion analysis and pulse shaping capabilities.
- Modeling the Interaction of Pulsed Wave Fields with Highly Contrasting Thin Layers
The time-domain analysis of wave field propagation in strongly heterogeneous media is of high practical importance in electromagnetics (with applications to finely layered integrated circuits and their signal integrity and EMC/EMI analysis) as well as in elastodynamics (with applications to oil and natural gas exploration). Accordingly, the present thesis aims at developing efficient computational models for calculating pulsed wave field responses of high-contrast thin-sheet onfigurations accounting for their relaxation behavior (e.g. plasmonic/meta-material thin layers).
- New active elements combining more ways of electronic control and their applications
This topic is focused on study of novel principles of electronic control in the frame of internal architecture of an active element. It extends performances of existing active elements such as: current conveyors, transconductors, current and voltage amplifiers, etc. These elements offer only one adjustable parameter in most cases. Main goals are identification of hitherto unpublished possibilities of the control in the frame of one block or simple combination of several basic sub-blocks. Investigation of this active device will be provided by ideal models, behavioral models (emulators) based on commercially available devices and their realization in suitable CMOS technology. Verification of usability of these active elements in suitable standard and smart circuit applications is also supposed.
- Novel methods for precise target location in active radars
This work is focused on research of novel radar signals and suited detecting techniques for more precise and ambiguous determination of radar targets. Searching of optimal combination of pulse radar signal (even more signals in cooperation) and filtering in detector for real targets and clutters is supposed.
- Optical Wireless Communication Based on Fully Photonic Technology
The object of this research project consists in developing new methods and techniques for the optical wireless links (OWL) based on the implementation of fiber elements into the communication chain. The aim of the project is to analyze OWL applications in transport telematics, to analyze atmospheric phenomena and to improve reliability of the link working in an unsteady and non-homogeneous atmosphere. The optimal wavelength of carrier regarding eye safety and atmospheric effects will be studied. Presented research is a part of the upcoming GACR grant project.
- Passive localization of experimental satellites in low earth orbits
The aim of the project is a study of actual signals from experimental satellites and its influence on localization. Part of the work will be a study of error sources as atmosperic influence and parameters of SDR receivers. Measurement with multiple of SDR receivers will follow to get experimental data for localization implementation. The research then will be targeted to optimal solutions for high precision, resolution and other parameters of realized system.
- Physical layer encryption
Physical layer encryption exploits quasi-random changes of physical channel parameters (polarization, frequency) to encrypt transmitted information. Quasi-random changes are specified by an encryption key on a chemical, magnetic, electrical or electromagnetic basis.
In the project, strategies for an efficient encryption on the physical layer (electromagnetic encryption) and the media access control layer (channel access encryption) will be investigated. New strategies combining encryption tools on both the layers will be the output of the project.
The described research is a part of a prepared grant project.
- Programmable microwave components
The project is focused on the research of microwave components which can be programmed to achieve required function depending on specific need. The attention should be particularly concentrated on the development of programmable transmission structures based on conventional or artificial materials. Proposed components should find application in the area of future wireless communication systems.
- Pulsed EM Wave Field On-Body Propagation
In contrast to what is presently being used in the relevant literature on the subject, the proper physical understanding of the body channel communication mechanism calls for its causality-preserving analytical description in the time domain. Accordingly, the research in the thesis will deal with the analysis of pulsed EM wave field propagation in the close vicinity of (a simplified model of) a human body. The validity of the proposed closed-form propagation models will be demonstrated by means of both numerical and real-life experiments.
- Receiving of very weak radiofrequency signals
Reception of microwave signals coming from the universe is characterized by very low Eb/N0 ratio. That is mostly concerned with phase or frequency shift keying of a carrier or sub-carrier. Reduced bandwidth is applied for AWGN elimination as the signal’s source increases. For this reason very high frequency stability has to be achieved by locking to an atomic frequency standard as well as precise compensation of Doppler shift. Basic requirement is a low value of equivalent system’s noise temperature achievement, related to optimized radiated pattern of the parabolic reflector feed. A part of the project is also methodology of the system sensitivity measurement by means of extraterrestrial noise sources.
- Sensing electromagnetic phenomena of animal brain
The project is aimed to investigate potential approaches to measurements of electromagnetic fields on the surface of an animal head, and to develop a solver of an inverse problem to determine equivalent currents inside the head.
In order to verify correctness of the solution of the inverse problem, a phantom of the animal head has to be developed enabling us to change currents inside the head deterministically, and to measure electromagnetic phenomena on the surface of the head.
The described research is a part of a prepared project to be solved in cooperation with the Center of Mental Health in Prague and Nencki Institute of experimental biology in Warsaw.
- Sensor networks for vehicles
One of the ways reducing the cost and consumption of cars, aircrafts, and other transport vehicles is the replacement of expensive and relatively heavy wiring harness interconnecting tens to hundreds of sensors and actuators with control unit by a wireless network. Multipath propagation of signals in a noisy environment and coordination of a mutual communication, however, requires the use of special techniques and signal processing algorithms. The aim of the project is design and optimization of the multi-hop sensor network. The appropriate modulation, methods of equalization and error correction, etc. on the physical layer and methods of communication resources allocation and coordination of data transfer at higher layers will be investigated.
- Signal Integrity Analysis for Pulse-Excited Antenna Arrays
The thesis aims at the development of a purely time-domain methodology capable of characterizing the performance of pulse-excited (ultra-wide band) antenna arrays. Namely, the emphasis is placed on the distortion in radiated EM signatures and its characterization by properly defined antenna-system fidelity factors accounting for such systems' beam-shaping and beam-steering capabilities.
The thesis will cover (1) analytical and numerical time-domain analyses of generic antenna elements; (2) general description of the pulsed EM-radiation characteristics of an antenna array in dependence on its configurational (e.g. positioning of antenna elements) and excitation parameters (e.g. the pulse shape of feeding electric currents); (3) analytical study into mutual EM space-time coupling between antenna elements; (4) illustrative parameter studies of selected antenna arrays validating the proposed concepts.
- Special advanced active elements in applications of digital modulations
This work is focused on study of utilization of special active elements and blocks in the designs of digital modulators and demodulators (for example: frequency hopping, phase shift keying, pulse width modulation, etc.) for structures of physical layer of communication systems working in base-band and inter-frequency band. Design of final applications supposes proposals of own network solutions of electronically controllable oscillators and generators of signals with specific output waveforms. One goal of this work consists in specification of parameters of active elements and blocks required for their utilization in such applications. Theoretical hypotheses will be verified by computer simulations and by experiments with commercially available elements (behavioral emulator), or eventually by simulations and realization of proposed systems in available CMOS technology (AMIS 0.35 um, TSMC 0.18 um).
- The Unexploded Ordnance Detection and Identification Based on Transient Radar Response Approximations
The prospective research will focus on the imaging potentialities of far-field monostatic pulsed radar returns from a buried unexploded ordnance. A successful completion of the thesis will result in (a) efficient analytical or/and numerical methods for transient EM scattering response calculations; (b) the reliable interpretation of target signatures and in (c) proposing a monostatic radar prototype with its pulse generator and transmitting/receiving antenna system.
- Tunability range extensions in electronically controllable circuits
Decreasing value of power supply voltage creates limited conditions for electronic tuning of circuits (for example active filters) in comparison to standard current systems operating with high DC power supply. The main task of this work focuses on research and study of methods of electronic control of applications (for example filters and oscillators) working as components of modern communication systems. Suitable combination of features for control of active elements and change of character of dependence (e.g. oscillation frequency vs. adjustable parameter) serve for substantial improvement of tunability range of application. Verification of intended methods supposes PSpice and Cadence IC6 (low voltage technologies AMIS 0.35 um, TSMC 0.18 um) simulations and experiments.
- Wireless networks for personal assistive technologies
Doctoral thesis is focused on analysis and modeling of the personal assistive technologies for people with sensorial or motoric handicap. Thesis deals with design of the wireless networks consist of video image and audio sensors and their connectivity into the Internet of Things (IoT) and according services. Optimization of the network regarding relevant features extraction from the captured data, its volume in the wireless network, energy balance and computing demands of the components at the same time with reliability of the present and future wireless networks coexistence are points to be investigated (WLAN, WRAN, LTE, BLE, ZigBee etc.). The aim of the work is experimental verification of the wireless network concept in selected use cases of the personal assistive system.