2000/2

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    Efficient Use of Mobile Radio Channels II
    (Společnost pro radioelektronické inženýrství, 2000-06) Danek, K.
    This paper is focused on the use of the mobile radio channels, comparing the efficiency of analog double-conversion superheterodyne receiver and software radio. The task of mutually comparing both technologies is made difficult by the possibility of implementing various decoding algorithms. Hence, the criterion of the dynamic range is being postulated as a basic comparison. The data-bearing signal which got degraded in sequel of unfit parameters - those which in their sum characterize the dynamic range of the receiver - cannot be renewed and faultlessly decoded anymore.
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    Magnetoliposome Mediated Local Electromagnetic Tumor Hyperthermia
    (Společnost pro radioelektronické inženýrství, 2000-06) Babincova, M.; Cicmanec, P.; Babinec, P.; Altanerova, V.; Altaner, C.
    Magnetoliposomes prepared by enwrapping 8 nm sized superparamagnetic magnetite grains with phospholipid bilayer were evaluated as possible new material for local electromagnetic hyperthermia both in vitro and in vivo after their injection into implanted BP-6 tumor in rats. As has been found the center of tumor is heated in 10 minutes from 35°C to 44.1°C using magnetic field with induction 1.5 mT and frequency 3.5 MHz.
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    Fundamentals of an Optimal Multirate Subband Coding of Cyclostationary Signals
    (Společnost pro radioelektronické inženýrství, 2000-06) Kula, D.
    A consistent theory of optimal subband coding of zero mean wide-sense cyclostationary signals, with N-periodic statistics, is presented in this article. An M-channel orthonormal uniform filter bank, employing N-periodic analysis and synthesis filters, is used while an average variance condition is applied to evaluate the output distortion. In three lemmas and final theorem, the necessity of decorrelation of blocked subband signals and requirement of specific ordering of power spectral densities are proven.
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    The Importance of Simulation Accuracy in Chaotic Circuits
    (Společnost pro radioelektronické inženýrství, 2000-06) Kvarda, P.
    In this paper an example of importance of the simulation accuracy in deterministic chaotic oscillators and other chaotic systems is briefly described and shown. Low accuracy in simulation may cause that the non-chaotic system may look chaotic or chaotic as non-chaotic. How we can prevent it is shown also in this work.
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    Resampling of an Image by Block-Based Interpolation or Decimation with Compensation
    (Společnost pro radioelektronické inženýrství, 2000-06) Zavacky, J.; Mihalik, J.; Kapinos, M.
    Due to multiple standards on digital coding of image it is expected that conversion from one picture format to another will be quite necessary for display or recording of different format sources. Conventional approach of 2-D sampling rate conversion by polyphase filters requires relatively large memory and computational power. Therefore, a new efficient method for image resampling has been presented. The proposed approach performs resampling block by block with overlap. To minimize the overlap special block interpolation kernels are used, with one pixel overlap gives satisfactory result for most of practical images. Proposed method can be efficiently applied to image communication systems where block transforms are used for data compression