Browsing 2012/4 by Title
Now showing items 1-20 of 45
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3-D Microwave Imaging for Breast Cancer
(Společnost pro radioelektronické inženýrství, 2012-12)We introduce a novel microwave imaging technique for breast cancer detection. Our approach provides a one-pass inverse image solution, which is completely new and unprecedented, unrelated to tomography or radar-based ... -
Analysis of Multipath Mitigation Techniques with Land Mobile Satellite Channel Model
(Společnost pro radioelektronické inženýrství, 2012-12)Multipath is undesirable for Global Navigation Satellite System (GNSS) receivers, since the reception of multipath can create a significant distortion to the shape of the correlation function leading to an error in the ... -
Analytical High-efficiency Spot beam Model for High Throughput Satellites
(Společnost pro radioelektronické inženýrství, 2012-12)We develop a simple model for a feed horn with a uniformly excited circular aperture at the focus of an offset paraboloidal reflector antenna and compare it with reflector antenna analyses using combinations of circular ... -
Antenna Design Concepts Based on Transformation Electromagnetics Approach
(Společnost pro radioelektronické inženýrství, 2012-12)Using the idea of wave manipulation via coordinate transformation, we demonstrate the design of novel antenna concepts. The manipulation is enabled by composite metamaterials that realize the space coordinate transformation. ... -
Application of Artificial Neural Networks for Efficient High-Resolution 2D DOA Estimation
(Společnost pro radioelektronické inženýrství, 2012-12)A novel method to provide high-resolution Two-Dimensional Direction of Arrival (2D DOA) estimation employing Artificial Neural Networks (ANNs) is presented in this paper. The observed space is divided into azimuth and ... -
Broadband Spectrum Survey Measurements for Cognitive Radio Applications
(Společnost pro radioelektronické inženýrství, 2012-12)It is well known that the existing spectrum licensing system results in a gross under-utilization of the frequency spectrum. Spectrum background measurements – spectrum surveys – provide useful data for spectrum regulation, ... -
Characterization of 60 GHz Shadowing by Human Bodies and Simple Phantoms
(Společnost pro radioelektronické inženýrství, 2012-12)The 60 GHz band is very prominsing for high data rate (>1 Gb/s) wireless systems operating at short ranges. However, due to the short wavelengths in this frequency band, the shadowing effects cuased by human bodies and ... -
Communication Subsystems for Emerging Wireless Technologies
(Společnost pro radioelektronické inženýrství, 2012-12)The paper describes a multi-disciplinary design of modern communication systems. The design starts with the analysis of a system in order to define requirements on its individual components. The design exploits proper ... -
Compact and High Performance Dual-band Bandpass Filter Using Resonator-embedded Scheme for WLANs
(Společnost pro radioelektronické inženýrství, 2012-12)A compact microstrip dual-band bandpass filter (DBBPF) with high selectivity and good suppression for wireless local area networks (WLANs) is proposed utilizing a novel embedded scheme resonator. Two passbands are produced ... -
Comparison of Planar Fractal Filters on Defected Ground Substrate
(Společnost pro radioelektronické inženýrství, 2012-12)The paper discusses approaches to the reduction of dimensions of planar filters (microstrip ones and coplanar ones). Filter dimensions are reduced by applying the fractal theory to the geometry of a filter, and by the ... -
CRLBs for Pilot-Aided Channel Estimation in OFDM System under Gaussian and Non-Gaussian Mixed Noise
(Společnost pro radioelektronické inženýrství, 2012-12)The determination of Cramer-Rao lower bound (CRLB) as an optimality criterion for the problem of channel estimation in wireless communication is a very important issue. Several CRLBs on channel estimation have been derived ... -
Current-Mode Universal Filters Employing Single FDCCII
(Společnost pro radioelektronické inženýrství, 2012-12)In this study, to realize current-mode multifunction filters, three new circuit configurations are presented. The circuits include fully differential current conveyor (FDCCII) and four passive components. First proposed ... -
Degenerate RFID Channel Modeling for Positioning Applications
(Společnost pro radioelektronické inženýrství, 2012-12)This paper introduces the theory of channel modeling for positioning applications in UHF RFID. It explains basic parameters for channel characterization from both the narrowband and wideband point of view. More details are ... -
Design of Multiple Trellis-Coded Multi-h CPM Based on Super Trellis
(Společnost pro radioelektronické inženýrství, 2012-12)It has been shown that the multiple trellis code can perform better than the conventional trellis code over AWGN channels, at the cost of additional computations per trellis branch. Multiple trellis coded multi-h CPM schemes ... -
Design, Fabrication and Properties of the Multimode Polymer Planar 1 x 2 Y Optical Splitter
(Společnost pro radioelektronické inženýrství, 2012-12)We report about design, fabrication and measurement of the properties of multimode 1 x 2 optical planar power splitter. The splitters were designed with help of OptiCAD software using ray tracing method. The dimensions of ... -
The Distribution of Minimum of Ratios of Two Random Variables and Its Application in Analysis of Multi-hop Systems
(Společnost pro radioelektronické inženýrství, 2012-12)The distributions of random variables are of interest in many areas of science. In this paper, ascertaining on the importance of multi-hop transmission in contemporary wireless communications systems operating over fading ... -
Empirical Modeling of Ducting Effects on a Mobile Microwave Link Over a Sea Surface
(Společnost pro radioelektronické inženýrství, 2012-12)In this paper, signal enhancement due to the ducts over a sea surface is experimentally investigated and modeled. The investigation is carried out through the study of air-to-ground mobile microwave links over a tropical ... -
Evolutionary Synthesis of Fractional Capacitor Using Simulated Annealing Method
(Společnost pro radioelektronické inženýrství, 2012-12)Synthesis of fractional capacitor using classical analog circuit synthesis method was described in [6]. The work presented in this paper is focused on synthesis of the same problem by means of evolutionary method simulated ... -
A Fast Frequency Sweep – Green’s Function Based Analysis of Substrate Integrated Waveguide
(Společnost pro radioelektronické inženýrství, 2012-12)In this paper, a fast frequency sweep technique is applied to the analysis of Substrate Integrated Waveguides performed with a Green’s function technique. The well-known Asymptotic Waveform Evaluation technique is used to ... -
Graph Cuts based Image Segmentation using Fuzzy Rule Based System
(Společnost pro radioelektronické inženýrství, 2012-12)This work deals with the segmentation of gray scale, color and texture images using graph cuts. From input image, a graph is constructed using intensity, color and texture profiles of the image simultaneously. Based on the ...