Wyniki wyszukiwania - BazTech

1

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

Hermanowicz E., Rojewski M.

International Journal of Electronics and Telecommunications

|

2014

|

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.

2

Wybrane zagadnienia projektowania i realizacji filtrów LC dla pasm poniżej 1 GHz

Rudziński A., Kozłowski S.

Elektronika : konstrukcje, technologie, zastosowania

|

2013

|

Vol. 54, nr 7

68-73

PL

Niniejszy artykuł omawia najistotniejsze zagadnienia praktyczne występujące przy projektowaniu filtrów LC. Wskazano podstawowe efekty o istotnym znaczeniu, które typowo pomija się w pracach teoretycznych, a które muszą być uwzględniane przez projektanta filtru.

EN

This paper discusses the most important practical problems related to design of LC filters. There are indicated fundamental effects of high importance, which are typically omitted in theoretical works, but must be considered by the designer of the filter.

3

New filter separation efficiency in CAN bus

Długosz T.

Przegląd Elektrotechniczny

|

2011

|

R. 87, nr 7

93-94

EN

Controller Area Network bus design in automobile need to take into account aspects on electromagnetic compatibility for components and system. With filter and connecting approaches considerations are presented in the work for protection of CAN bus system.

PL

Proces projektowania magistrali komunikacyjnych CAN wymaga uwzględnienia zagadnień kompatybilnościowych i odpowiednich wymogów dotyczących zarówno poszczególnych komponentów, jak i całego systemu. Niniejszy artykuł dotyczy projektowania filtrów mających na celu ochronę magistrali CAN przed zakłóceniami elektromagnetycznymi

4

Dobór wybranych parametrów algorytmu genetycznego na przykładzie projektowania filtrów

Rutczyńska-Wdowiak K.

Logistyka

|

2010

|

nr 6

PL

Praca przedstawia rezultaty zastosowania algorytmu genetycznego (AG) w problemie projektowania filtru cyfrowego na przykładzie jego prototypu analogowego. Wybór AG wynika z faktu, że algorytm ten przez losowy wybór dostatecznie wielu reprezentantów populacji zapewnia większą szansę wyznaczenia minimum globalnego, niż metody klasyczne. W pracy wykorzystano algorytm genetyczny oparty na reprezentacji zmiennopozycyjnej osobników, selekcji turniejowej z częściową wymianą populacji, krzyżowaniu arytmetycznym oraz mutacji równomiernej [1]. Badania koncentrowały się na doborze odpowiednich wartości parametrów AG, takich jak: rozmiar populacji oraz przestrzeń poszukiwań rozwiązania. Analizowano wybraną metodę genetyczną z uwagi na zbieżność, dokładność i czas obliczeń numerycznych.

EN

This paper presents the results of genetic algorithm (GA) application in design of digital filter based on analog prototype. The GA through the random choice of a sufficient number of representatives searches within the whole population of potential solutions and therefore the chance of determining the local minimum instead of the global one is considerably smaller than in case of using of classical methods. In this work the genetic algorithm based on a floating point representation of individuals, tournament selection with steady-state, arithmetical crossover and uniform mutation [1] was used. The results of research of the influence of GA parameters' values, such as: population size and search space on process of searching the solution were presented. The analysis of genetic method with regard to convergence and accuracy for the process of searching solution and time of numerical calculations was carried out.

5

Usefulness of the fiber-optic interferometer for the investigation of the seismic rotation waves

Jaroszewicz L., Krajewski Z., Teisseyre R.

Optica Applicata

|

2005

|

Vol. 35, nr 2

383-394

EN

In the paper new areas of the fiber-optic Sagnac interferometer applications are discussed and proposed. Because this system detects the absolute rotation, its application is directly designed for detection of the seismic rotation waves which are rotational events existing in the seismic waves. In most cases those waves are extracted from recordings of differential seismic signals. However, all differences in responses of the seismometers cause disturbances which obscure these hidden components as it is for two antiparallel pendulum seismometers (TAPS) system. The presented device, named fiber-optic rotational seismometer (FORS), is free from this disadvantage and may be used for other rotational seismometer calibration, as well as for direct seismic rotation waves detection. The paper describes the design based on a well-known optical gyroscope configuration but with its optimization for its optimization for detection the absolute rotation, only. The obtained results have been the source of TAPS work improvement by applying the data smoothing by a spline function. Moreover, the first application of FORS for recording rotational parts existing in the seismic events has shown that they probably propagate with different velocity than classical earthquake waves.

6

Time-domain filtering of seismic rotation waves

Nowożyński K., Teisseyre K.

Acta Geophysica Polonica

|

2003

|

Vol. 51, nr 1

51-61

EN

Rotational parts of seismic waves are extracted from recordings of differential seismic signals. Thus, all differences in responses of the seismometers cause disturbances which obscure these hidden components. The method of removing great part of these disturbances is developed, based on the time-domain filtering and using the data collected over a selected period of seismic monitoring called the test phase. Examples of seismic rotation components for some events registered in the Ojców observatory are shown, together with results of checking the adequacy of the presented method.

7

Zastosowanie algorytmów genetycznych do projektowania filtrów dyskretnych

Wyrwał S.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

|

2002

|

Vol. 284, z. 52

137-152

PL

Artykuł opisuje zastosowanie algorytmów genetycznych do projektowania filtra o nieskończonej odpowiedzi impulsowej przy założonej topologii tego filtra.

EN

Genetic Algorithm is used to solve an Infinite Impulse Response (IIR) filter design problem. The architecture of the filter is assumed.

8

Determination and processing of measuring equipment responses

Nowożyński K.

Acta Geophysica Polonica

|

2001

|

Vol. 49, nr 3

389-413

EN

The aim of this paper is to present algorithms useful in determination of measuring equipment responses. It shows how the phase and amplitude response of a device can be determined. Taking benefit of a digital FIR filter equivalent to the device, the paper discusses different ways of finding such filters as to eliminate or modify the effect of the device on the recorded data. Determination of equipment response is understood to be both the determination of response in the frequency domain and finding the coefficients of a filter equivalent to the device.