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1

Determination of measurement uncertainty by a Monte Carlo method for an RF power sensor calibration system using a VNA

Jaworski Marek, Szatkowski Jarosław, Kossek Tomasz

Metrology and Measurement Systems

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2023

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Vol. 30, nr 4

703--720

EN

This work proposes a systematic assessment of measuring type A uncertainty (caused by random errors) used in RF power sensor calibration. To reduce A type uncertainty, several successive measurements are repeated. The uncertainty arises from repeatability errors in connectors caused by changes in their electrical properties during repeated mating. The suitability of the METAS UncLib software was analysed and we concluded that software should be developed to take into account the shape of probability density function (PDF) using a Monte Carlo method (MCM), which was lacking in METAS UncLib. The self-developed software was then tested on an example taken from the literature and the superiority of the MCM over the analytical method (GUM) was confirmed. During the calibration of the RF sensor using a vector network analyzer (VNA), a series of repeated measurements were performed and, after applying our MCM software, it was found that the measurement uncertainties calculated by the MCM method were several times larger than those by the GUM. The reason for this was that the correlation between the measured input quantities was not taken into account. When this was done using a covariance matrix and assuming a normal PDF of the input quantities, the results obtained with the GUM and the MCM converged. Our main objective was to investigate the influence of the PDF shape of the input measurement samples on the measurement uncertainty. Taking more than a dozen measurements is too costly, on the other hand, the small sample size prevents a reliable determination of the PDF shape. Finally, to overcome this inconvenience, we have developed a special method that uses the histograms of standardized input data taken at all measurement frequencies under fixed conditions without disconnecting the connectors, to increasing the total number of results which were needed to create the PDF histograms of input quantities.

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NATO standardization documents for mine countermeasure and their updating as an area of scientific activity

Listewnik K., Kubis P.

Zeszyty Naukowe Akademii Marynarki Wojennej

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2018

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R. 59 nr 1 (212)

69--84

EN

NATO standardization documents are the basis for action in many areas of NATO military activity and their affiliated organizations. The development of the NATO standardization documentation has been on-going for more than 60 years, and their content provides a reliable basis for joint action in a unified manner, enabling interoperability in many areas of NATO operations. The article is divided into three parts, the first of which deals with the general principles of NATO standardization, the second part describes the standardization documents related to the measurement of the ship’s signatures in aspect of the mine countermeasures and the third describes the participation in research project of NATO — RIMPASSE 2011 Trial. One of the their task was to verify and update NATO standardization documents including AMP-15.

PL

Dokumenty standaryzacyjne NATO są podstawą działania w wielu obszarach aktywności wojsk NATO i stowarzyszonych z nimi organizacji. Rozwój dokumentacji standaryzacyjnej NATO trwa od ponad sześćdziesięciu lat i ich zawartość stanowi rzetelną podstawę do wspólnego działania w zunifikowany sposób, umożliwiając interoperacyjność w wielu dziedzinach działań wojsk NATO. Artykuł podzielono na trzy części, z których pierwsza przybliża ogólne zasady normalizacji w NATO, druga zawiera opis dokumentów standaryzacyjnych związanych z pomiarami pól fizycznych okrętu oraz obroną przeciwminową, trzecia zaś opisuje udział w projekcie badawczym NATO — badania RIMPASSE 2011, którego jednym z zadań była weryfikacja i aktualizacja dokumentów standaryzacyjnych NATO, w tym AMP-15.

3

Overlapped filtered multitone modulation and its optimization on VLIW DSP

Silhavy P., Krajsa O., Systel P., Koutny M.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 12a

145-149

EN

In recent years, the multicarrier modulations (MCM) have been applied to wire and wireless transmission systems. MCM enable a nearperfect utilization of the provided frequency band on metallic cables and they also effectively eliminate multipath propagation in terrestrial transmission. They are mainly the implementations called Discrete MultiTone (DMT) and Orthogonal Frequency Division Multiplexing (OFDM). These approaches have also disadvantages, which have led to seeking new approaches to the implementation of the MCM modulation scheme. One of them is the Filtered MultiTone Modulation (FMT). In the article, the channel equalization in overlapped and non-overlapped FMT modulation will be compared. The optimal implementation of FMT on the VLIW DSP will be introduced in the second part.Optimized implementation of filter bank with the help of parallel processing is described, and also frame writing/reading and its synchronization are introduced.

PL

W ostatnich latach, w modulacjach multicarrier (MCM) zostały zastosowane systemy transmisji przewodowej i bezprzewodowej. MCM umożliwiają niemal perfekcyjne wykorzystanie pasma częstotliwości przewidziane w kablach a również skutecznie wyeliminować wielodrogowość w transmisji naziemnej. Są to przede wszystkim implementacje o nazwie Discrete wielotonowy (DMT) i Orthogonal Frequency Division Multiplexing (OFDM). Metody te mają także wady, które doprowadziły do poszukiwania nowych sposobów podejściacia do wdrożenia systemu modulacji MCM. Jednym z nich jest filtrowane wielotonowe modulacji (FMT). W drugiej częścici artykułu została opisana optymalna implementacja modulacji FMT. Wykorzystano bank filtrów z równoległym przetwarzaniem, oraz odpowiednie ramki zapisu/odczytu oraz synchronizacji.