Wyniki wyszukiwania - BazTech

1

The decision-feedback equalizer optimization for Gaussian noise

Grzybowski A., Kisilewicz J. W.

Journal of Theoretical and Applied Computer Science

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2014

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Vol. 8, nr 4

5-12

EN

The new method of decision-feedback parameters optimization for intersymbol interference equalizers is described in this paper. The error extension phenomena is well known and investigated in the decision feedback equalizers in data transmission. The existing coefficient in decision feedback depends on the receive decision risk qualification. There is proved the bit error probability can be decreased by this method for any channel with single interference sample and small Gaussian noise. The experimental results are presented for chosen type channels. The dependences of optimal feedback parameters on channel interference sample and on noise power are presented too.

2

Square Root Raised Cosine Fractionally Delaying Nyquist Filter : Design and Performance Evaluation

Hermanowicz E., Rojewski M.

International Journal of Electronics and Telecommunications

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2014

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Vol. 60, No. 3

247-252

EN

In this paper we propose a discrete-time FIR (Finite Impulse Response) filter which is meant to be applied as a square root Nyquist filter and fractional delay filter simultaneously. The filter enables to substitute for a cascade of square root raised cosine (SRRC) Nyquist filter and fractional delay filter in one device/algorithm. The aim is to compensate for transmission delay in digital communication system. Performance of the filter in the role of a matched filter is evaluated using a newly defined energetic ISI (Intersymbol Interference) measure and ability of the filter to completely eliminate the ISI involved by fractional delay of symbol shaping filter in transmitter or by channel delay. Considerations and results of the contribution are documented by suitable eye-diagrams and the SRRC filter responses.

3

Optimal erasures in decision-feedback equalization for the Gaussian noise

Kisilewicz J. W., Grzybowski A.

International Journal of Applied Mathematics and Computer Science

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2006

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Vol. 16, no 1

147-154

EN

A new method of optimizing decision feedback parameters for intersymbol interference equalizers is described. The coefficient existing in the decision feedback loop depends on risk qualification of the received decision. We prove that bit error probability can be decreased with this method for any channel with a single interference sample and small Gaussian noise. Experimental results are presented for selected channels. The dependences of optimal feedback parameters on channel interference samples and noise power are presented, too.

4

Optymalizacja parametrów decyzyjnego sprzężenia zwrotnego

Grzybowski A., Kisilewicz J.

Zeszyty Naukowe. Informatyka / Politechnika Opolska

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2001

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Vol. 282, z. 1

93-109

PL

W pracy zaproponowano nowy algorytm korekcji interferencji międzysymbolowej w układzie z decyzyjnym sprzężeniem zwrotnym. Odbierane dane binarne są kwalifikowane jako mniej lub bardziej wiarygodne. Stopień kompensacji interferencji od odebranych danych uzależniono od wiarygodności tych danych. Dla kanałów z jednym prążkiem interferencyjnym oraz białym szumem gaussowskim wyznaczono optymalny próg kwalifikowania decyzji w funkcji współczynnika kompensacji. Przedstawione wyniki symulacji pozwalają określić optymalny współczynnik kompensacji i próg kwalifikacji wiarygodności decyzji w zależności od wartości prążka interferencyjnego kanału.

EN

The new algorithm of intersymbol interference equalization using decision feedback is proposed in this paper. The receiving data are qualified as less or more reliable. The incoming interference compensation coefficient depends on this reliable qualification. The optimal level for reliable qualification is evaluated as a function of compensation coefficient for channels with the single interference sample and white Gaussian noise. The simulation results are presented. This results can be useful for optimal compensation coefficient and optimal qualification level finding depending on interference sample value of the channel.