Wyniki wyszukiwania - BazTech

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Możliwości zamiany elektrycznych przepływomierzy powietrza stosowanych w silnikach spalinowych samochodów

Otta Robert, Świsulski Dariusz, Golijanek-Jędrzejczyk Anna

Przegląd Elektrotechniczny

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2021

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R. 97, nr 5

82--89

PL

W artykule przedstawiono podstawowe typy przepływomierzy powietrza, stosowane w silnikach spalinowych samochodów: z klapą spiętrzającą, HLM, HFM, Vortex i MAP. Przedstawiono wyniki badania tych przepływomierzy na specjalnie przygotowanym stanowisku pomiarowym. Przeanalizowano możliwość ich zamiany i zweryfikowano taką możliwość w praktyce.

EN

The article presents the basic types of air flow meters used in internal combustion engines of cars: with a damming flap, HLM, HFM, Vortex and MAP. The results of testing these flow meters on a specially prepared measuring stand are presented. The possibility of replacing them has been analyzed and this possibility has been verified in practice.

2

Measurement of impulse response of shallow water communication channel by correlation method

Schmidt J., Kochańska I., Schmidt A.

Hydroacoustics

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2017

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Vol. 20

149--158

EN

Performances of underwater acoustic communication (UAC) systems are strongly related to specific propagation conditions of the underwater channel; conditions that can additionally change in time due to the movement of the acoustic system transmitter and receiver or to reflection by underwater objects of the transmitted signal. The time-varying impulse response is a comprehensive description of dynamically changing transmission properties of the UAC channel. It is a basis for estimation of stochastic parameters used for designing the signaling scheme of the communication system. The paper presents the results of a measurement experiment conducted in a shallow water environment. The channel impulse response was measured by the correlation method with the use of two kinds of broadband signals: pseudo-random binary sequence (PRBS) and hyperbolic frequency modulation chirp (HFM). For each measurement result statistical transmission parameters, namely delay spread, Doppler spread, coherence time, and coherence bandwidth were estimated.

3

Mutual Clutter Suppression Techniques for FM Sonars

Marszal J., Rudnicki M., Jedel A., Salamon R., Kochańska I.

Archives of Acoustics

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2016

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Vol. 41, No. 4

721--729

EN

The article presents methods that help in the elimination of mutual clutter as well as the consequences of two FM sounding signal sonars operating in the same body of water and frequency band. An in-depth analysis of mutual clutter was carried out. The effects of sounding signal differentiation were determined, as was the Doppler effect on mutual clutter suppression. One of the methods analysed is of particular interest in a situation in which collaborating sonars are operating in opposite frequency modulation directions. This method is effective for both linear and hyperbolic frequency modulations. A formula was derived, identifying exactly how much quantities of clutter may be lessened. The work included comprehensive computer simulations and measurements as well as tests in real-life conditions.