1998/4

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Now showing 1 - 5 of 9
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    An Ischemic Disease Classification of Lower Limbs
    (Společnost pro radioelektronické inženýrství, 1998-12) Rozman, J.; Zona, M.; Peroutik, J.
    An ischemic disease of lower limbs is a manifestation of general arteriosclerosis. Its early noninvasive diagnostic is possible using the approach of the Doppler measurement of the blood flow in the vessels with following classification by a neural network expert system.
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    Rain Scattering and Co-ordinate Distance Calculation
    (Společnost pro radioelektronické inženýrství, 1998-12) Hajny, M.
    Calculations of scattered field on the rain objects are based on using of Multiple MultiPole (MMP) numerical method. Both bi-static scattering function and bi-static scattering cross section are calculated in the plane parallel to Earth surface. The co-ordination area was determined using the simple model of scattering volume [1]. Calculation for frequency 9.595 GHz and antenna elevation of 25° was done. Obtained results are compared with calculation in accordance to ITU-R recommendation.
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    ARC Filters with Diamond Transistors and Buffers
    (Společnost pro radioelektronické inženýrství, 1998-12) Dostal, T.
    Active RC first and second order filters using diamond transistors (voltage controlled current sources) and voltage diamond buffers (voltage controlled voltage sources) are given in this paper. Circuits are simulated and experimentally compared.
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    Study of 2-input 2-output Blind Signal Separation by Output Decorrelation
    (Společnost pro radioelektronické inženýrství, 1998-12) Machuca, E.; Sovka, Pavel; Davidek, V.
    The simulations and experiments representing the initial study of the output decorrelation approach to blind signal separation are presented in this paper. The definition of performance indexes for the evaluation and comparison of different algorithms are proposed. Two algorithms are compared. Some first results of real experiments are discussed.
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    Differential GMSK Receivers with Phase Control for Narrowband Radio Communications
    (Společnost pro radioelektronické inženýrství, 1998-12) Mahdavi, A.; Gordon, D.; Riley, N.
    An implementation method for differential Gaussian Minimum Shift Keying receivers with Phase Control is presented. It is shown that in such receivers the effect' of InterSymbol Interference (ISI) on the signal, caused by the adjacent bits is reduced by introducing Phase Control in accordance with the data stream. This results in improved system performance, particularly at low values of time-bandwidth product of the premodulation gaussian filter where ISI is high. With the application of this technique the performance of differential receiver is enhanced to a level where it is comparable to that of coherent receiver and yet avoids the problems associated with the complex carrier recovery in the latter case.