Посмотр 2010/2 по дате публикации
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Transmission Line on Semiconductor Substrate with Distributed Amplification
(Společnost pro radioelektronické inženýrství, 2010-06)In order to compensate losses in metal strips, an active microstrip line on a semiconductor substrate is proposed, and its finite element model is presented. The active medium is provided by A3B5 semiconductor in highintensity ... -
Comparison of Constant and Temperature Dependent Blood Perfusion in Temperature Prediction for Superficial Hyperthermia
(Společnost pro radioelektronické inženýrství, 2010-06)The purpose of this study was to determine whether prediction of the 3D temperature profile for superficial hyperthermia using constant blood perfusion model could be matched to one with a temperature dependent blood ... -
Simulation and Measurement of the Transmission Distortions of the Digital Television DVB-T/H (Part 1: Modulator for Digital Terrestrial Television)
(Společnost pro radioelektronické inženýrství, 2010-06)The paper deals with the first part of results of the Czech Science Foundation research project that was aimed into the simulation and measurement of the transmission distortions of the digital terrestrial television ... -
A Novel Technique of Error Concealment Method Selection in Texture Images Using ALBP Classifier
(Společnost pro radioelektronické inženýrství, 2010-06)There are many error concealment techniques for image processing. In the paper, the focus is on restoration of image with missing blocks or macroblocks. Different methods can be optimal for different kinds of images. In ... -
Quasi Cyclic Low Density Parity Check Code for High SNR Data Transfer
(Společnost pro radioelektronické inženýrství, 2010-06)An improved Quasi Cyclic Low Density Parity Check code (QC-LDPC) is proposed to reduce the complexity of the Low Density Parity Check code (LDPC) while obtaining the similar performance. The proposed QC-LDPC presents an ... -
Estimation of the EMI Filter Circuitry from the Insertion Loss Characteristics
(Společnost pro radioelektronické inženýrství, 2010-06)The paper deals with the EMI filter models for the calculation of the insertion loss characteristics. The insertion loss is in fact the basic EMI filter property. Unfortunately it is not easy to precisely define and measure ... -
Modeling of 830 nm FSO Link Attenuation in Fog or Wind Turbulence
(Společnost pro radioelektronické inženýrství, 2010-06)This study is focused on the experimental research of the atmosphere impact on FSO link attenuation. Experiment is performed on a mountain observatory Milesovka of severe weather conditions. The empirical relationships on ... -
The Effects of Weather on the Life Time of Wireless Sensor Networks Using FSO/RF Communication
(Společnost pro radioelektronické inženýrství, 2010-06)The increased interest in long lasting wireless sensor networks motivates to use Free Space Optics (FSO) link along with radio frequency (RF) link for communication. Earlier results show that RF/FSO wireless sensor networks ... -
Adaptive Bit Rate Video Streaming Through an RF/Free Space Optical Laser Link
(Společnost pro radioelektronické inženýrství, 2010-06)This paper presents a channel-adaptive video streaming scheme which adjusts video bit rate according to channel conditions and transmits video through a hybrid RF/free space optical (FSO) laser communication system. The ... -
Filtering Technique for Stabilization of Marching-on-in-Time Method
(Společnost pro radioelektronické inženýrství, 2010-06)In this paper, digital filters are used for the stabilization of the marching-on-in-time (MOT) method. A methodology of designing a proper filter using optimization techniques is proposed here. Since the proposed procedure ... -
Wave Propagation in Lossy and Superconducting Circular Waveguides
(Společnost pro radioelektronické inženýrství, 2010-06)We present an accurate approach to compute the attenuation of waves, propagating in circular waveguides with lossy and superconducting walls. A set of transcendental equation is developed by matching the fields at the ... -
A Novel OFDM Channel Estimation Algorithm with ICI Mitigation over Fast Fading Channels
(Společnost pro radioelektronické inženýrství, 2010-06)Orthogonal frequency-division multiplexing (OFDM) is well-known as a high-bit-rate transmission technique, but the Doppler frequency offset due to the high speed movement destroys the orthogonality of the subcarriers ... -
Dense Maritime Fog Attenuation Prediction from Measured Visibility Data
(Společnost pro radioelektronické inženýrství, 2010-06)The benefits of Free Space Optics (FSO) motivate to use it for future high data rate demanding communication applications. However, widespread growth of the technology has been hampered by reduced availability due to weather ... -
PDF Estimation and Liquid Water Content Based Attenuation Modeling for Fog in Terrestrial FSO Links
(Společnost pro radioelektronické inženýrství, 2010-06)Terrestrial Free-space optical communication (FSO) links have yet to achieve a mass market success due to the ever elusive 99.999% availability requirement. The terrestrial FSO links are heavily affected by atmospheric ... -
Anonymous Authentication for Smartcards
(Společnost pro radioelektronické inženýrství, 2010-06)The paper presents an innovative solution in the field of RFID (Radio-Frequency IDentification) smartcard authentication. Currently the smartcards are used for many purposes - e.g. employee identification, library cards, ... -
Electronically Tunable Third-Order Quadrature Oscillator Using CDTAs
(Společnost pro radioelektronické inženýrství, 2010-06)A current/voltage-mode third-order quadrature oscillator based on current differencing transconductance amplifiers (CDTAs) is presented in this paper. Outputs of two current-mode and two voltage-mode sinusoids each with ... -
A Study of Fog Characteristics using Free-Space Optical Wireless Links
(Společnost pro radioelektronické inženýrství, 2010-06)A technique for modeling the fog droplet size distributions using modified gamma distribution has been demonstrated by considering two separate radiation fog events recorded in Graz (Austria) and Prague (Czech Republic). ... -
An Introduction to Free-space Optical Communications
(Společnost pro radioelektronické inženýrství, 2010-06)Over the last two decades free-space optical communication (FSO) has become more and more interesting as an adjunct or alternative to radio frequency communication. This article gives an overview of the challenges a system ... -
Exploiting of the Compression Methods for Reconstruction of the Antenna Far-Field Using Only Amplitude Near-Field Measurements
(Společnost pro radioelektronické inženýrství, 2010-06)The novel approach exploits the principle of the conventional two-plane amplitude measurements for the reconstruction of the unknown electric field distribution on the antenna aperture. The method combines a global ... -
Kalman Filter Aided Cooperative Optical Beam Tracking
(Společnost pro radioelektronické inženýrství, 2010-06)In free-space optical communication between mobile terminals relative motion of the terminals requires an active mechanism to maintain optical alignment between the stations. Cooperative optical beam tracking could be used ...