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1

IR detection module with integrated real-time FIR filter implemented in FPGA

Achtenberg Krzysztof, Mikołajczyk Janusz, Bielecki Zbigniew

International Journal of Electronics and Telecommunications

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2024

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Vol. 70, No. 1

175--182

EN

Infrared detectors are usually characterized by 1/f noise when operating with biasing. This type of noise significantly reduces detection capabilities for low-level and slow signals. There are a few methods to reduce the influence of 1/f noise, like filtering or chopper stabilization with lock-in. Using the first one, a simple 1st-order analog low-pass filter built-in amplifier usually cuts off 1/f noise fluctuations at low frequencies. In comparison, the stabilization technique modulates the signal transposing to a higher frequency with no 1/f noise and then demodulates it back (lock-in amplifiers). However, the flexible tuned device, which can work precisely at low frequencies, is especially desirable in some applications, e.g., optical spectroscopy or interferometry. The paper describes a proof-of-concept of an IR detection module with an adjustable digital filter taking advantage of finite impulse response type. It is based on the high-resolution analog-to-digital converter, field-programmable gate array, and digital-to-analog converter. A microcontroller with an implemented user interface ensures control of such a prepared filtering path. The module is a separate component with the possibility of customization and can be used in experiments or applications in which the reduction of noises and unexpected interferences is needed.

2

Application of cross-correlation-based transimpedance amplifier in InAs and InAsSb IR detectors noise measurements

Achtenberg Krzysztof, Mikołajczyk Janusz, Bielecki Zbigniew

Opto-Electronics Review

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2022

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Vol. 30, No. 2

art. no. e141126

EN

The paper presents noise measurements in low-resistance photodetectors using a crosscorrelation-based transimpedance amplifier. Such measurements usually apply a transimpedance amplifier design to provide a current fluctuation amplification. In the case of low-resistance sources, the measurement system causes additional relevant system noise which can be higher than noise generated in a tested detector. It mainly comes from the equivalent input voltage noise of the transimpedance amplifier. In this work, the unique circuit and a three-step procedure were used to reduce the floor noise, covering the measured infrared detector noise, mainly when operating with no-bias or low-bias voltage. The modified circuit and procedure to measure the noise of unbiased and biased detectors characterized by resistances much lower than 100 Ω were presented. Under low biases, the reference low-resistance resistors tested the measurement system operation and techniques. After the system verification, noise characteristics in low-resistance InAs and InAsSb infrared detectors were also measured.

3

Review of photodetectors characterization methods

Bielecki Zbigniew, Achtenberg Krzysztof, Kopytko Małgorzata, Mikołajczyk Janusz, Wojtas Jacek, Rogalski Antoni

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

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Vol. 70, nr 2

art. no. e140534

EN

The review includes results of analyses and research aimed at standardizing the concepts and measurement procedures associated with photodetector parameters. Photodetectors are key components that ensure the conversion of incoming optical radiation into an electrical signal in a wide variety of sophisticated optoelectronic systems and everyday devices, such as smartwatches and systems that measure the composition of the Martian atmosphere. Semiconductor detectors are presented, and they play a major role due to their excellent optical and electrical parameters as well as physical parameters, stability, and long mean time to failure. As their performance depends on the manufacturing technology and internal architecture, different types of photodetectors are described first. The following parts of the article concern metrological aspects related to their characterization. All the basic parameters have been defined, which are useful both for their users and their developers. This allows for the verification of photodetectors’ workmanship quality, the capabilities of a given technology, and, above all, suitability for a specific application and the performance of the final optoelectronic system. Experimentally validated meteorological models and equivalent diagrams, which are necessary for the correct analysis of parameter measurements, are also presented. The current state of knowledge presented in recognized scientific papers and the results of the authors’ works are described as well.

4

Review of peak signal detection methods in nanosecond pulses monitoring

Achtenberg Krzysztof, Mikołajczyk Janusz, Szabra Dariusz, Prokopiuk Artur, Bielecki Zbigniew

Metrology and Measurement Systems

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2020

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Vol. 27, nr 2

203--218

EN

The paper is a review of analog and digital electronics dedicated to monitor nanosecond pulses. Choosing the optimal peak detector construction depends on many factors for example precision, complexity, or costs. The work shows some virtues and limitations of selected peak detection methods, for example standard peak detector with rectifier, sample and hold circuit with triggering units and ADC fast acquisition. However, the main attention is paid to problems of results from effective triggering signal for sample and hold operation. The obtained results allow for designing a peak detector construction as an alternative for costly and very complex fast acquisition systems based on ADC and FPGA technologies.

5

FET input voltage amplifier for low frequency noise measurements

Achtenberg Krzysztof, Mikołajczyk Janusz, Bielecki Zbigniew

Metrology and Measurement Systems

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2020

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Vol. 27, nr 3

531--540

EN

The paper presents a low noise voltage FET amplifier for low frequency noise measurements. It was built using two stages of an op amp trans impedance amplifier. To reduce voltage noise, eight-paralleled low noise discrete JFETs were used in the first stage. The designed amplifier was then compared to commercial ones. Its measured value of voltage noise spectral density is around 24 nV/√Hz, 3 nV/√Hz, 0.95 nV/√Hz and 0.6 nV/√Hz at the frequency of 0.1, 1, 10 and 100 Hz, respectively. A -3dB frequency response is from ~20 mHz to ~600 kHz.

6

Hydromorphological Index for Rivers (HIR): A New Method for Hydromorphological Assessment and Classification for Flowing Waters in Poland

Szoszkiewicz Krzysztof, Jusik Szymon, Gebler Daniel, Achtenberg Krzysztof, Adynkiewicz-Piragas Mariusz, Radecki-Pawlik Artur, Okruszko Tomasz, Giełczewski Marek, Marcinkowski Paweł, Pietruczuk Karol, Przesmycki Marcin, Nawrocki Przemysław, Chmist Joanna, Szostak Marta

Journal of Ecological Engineering

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2020

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Vol. 21, nr 8

261--271

EN

The method based on original metric called Hydromorphological Index for Rivers (HIR) was developed in 2017 for the purpose of the monitoring of the hydromorphological status of flowing waters in Poland. It fulfils the requirements of the EU Water Framework Directive (WFD). It allows the assessment of both lowland rivers as well as mid-altitude and highland streams. The proposed system can be used to assess the natural and heavily modified rivers as well as artificial channels. The basis of the proposed system is a field survey, which is supplemented by the analysis of Geographic Information Systems (GIS) data and remote sensing materials. The analysis of the GIS data and remote sensing materials already enable to estimate preliminary classification of the hydromorphological status of the non-surveyed water bodies. On the basis of the field survey, the principal HIR value can be estimated for the considered river site and comparing with the reference conditions, the hydromorphological quality status in the five-class system can be calculated. The properly selected, representative survey sites (one or more depending on the heterogeneity of the environment), enable the classification and evaluation of entire surface water bodies in the framework of the national environmental monitoring. The GIS component of the HIR proved to be useful in verifying the determination of heavily modified water bodies and in assessing the needs of river restoration. It was also applied in the development of the National river restoration program for predicting the impact of the proposed restoration measure on the state of hydromorphology.

7

Optical Wireless Communications Operated at Long-Wave Infrared Radiation

Mikolajczyk Janusz, Szabra Dariusz, Prokopiuk Artur, Achtenberg Krzysztof, Wojtas Jacek, Bielecki Zbigniew

International Journal of Electronics and Telecommunications

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2020

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Vol. 66, No. 2

383--387

EN

This paper presents some construction analysis and test results of a Free Space Optics system operating at the wavelength of 9.35 μm. In the system, a quantum cascade laser and a photoreceiver with mercury cadmium telluride photodetectors were used. The main parameters of these elements were discussed taking into account a data link operation. It also provides to determine a data range for various weather conditions related to scattering and scintillation. The results of numerical analyses defined the properties of currently available FSO technologies working in the near infrared or in the short infrared range of spectrum versus the performances of the developed system. The operation of this system was verified in three different test environments. The obtained results may also contain important issues related to the practical application of any FSO system.

8

Korelacyjny pomiar gęstości widmowej mocy szumów detektorów fotonowych do spektroskopii absorpcyjnej

Achtenberg Krzysztof, Mikołajczyk Janusz, Bielecki Zbigniew, Wojtas Jacek

Biuletyn Wojskowej Akademii Technicznej

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2020

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Vol. 69, nr 4

73--83

PL

W pracy przedstawiono wyniki pomiarów gęstości widmowej napięcia szumów detektorów fotonowych o małych rezystancjach przy użyciu specjalnie opracowanego stanowiska pomiarowego. Badania tych detektorów mają duże znaczenie dla wielu aplikacji. Są one szczególnie istotne dla układów laserowej spektroskopii absorpcyjnej do wykrywania śladowych ilości gazów. Uzyskiwana w nich granica wykrywalności jest bezpośrednio związana nie tylko z szumami źródeł promieniowania i szumem tła, lecz także z szumami detektora oraz kolejnych stopni fotoodbiornika. Zastosowanie w opracowanym systemie specjalnie zaprojektowanych ultramałoszumowych torów pomiarowych (wzmacniacze o napięciu szumów 3,6 × 10⁻¹⁹ V²/Hz dla f > 1 kHz) oraz operacji korelacji sygnałów w czasie 10 minut umożliwiło uzyskanie szumu tła poniżej 10⁻¹⁸ V²/Hz dla f > 10 Hz oraz poniżej 10⁻¹⁹ V²/Hz dla f > 1 kHz. Efektywność systemu zweryfikowano poprzez pomiary referencyjnych rezystorów, a następnie detektora z supersieci drugiego rodzaju (T2SL) wykonanego z InAs/InAsSb.

EN

The paper presents noise measurements of low-resistance photon detectors with a specially developed system. These measurements are significant for many applications. This issue is particularly critical for laser absorption spectroscopy systems to detect trace amounts of gases. In these systems, the detection limit is determined by noise origins, e.g., light source, background, and detector noise and its readout electronics. The use of some specially designed components of the system (low-noise - 3.6 × 10⁻¹⁹ V²/Hz for f >1 kHz) cross-correlation signal processing provides to obtain a measuring floor noise below 10⁻¹⁸ V²/Hz for f > 10 Hz and below 10⁻¹⁹ V²/Hz for f > 1 kHz after ten minutes’ analysis. Measurements of some reference resistors have verified the system’s performance. Finally, the system was also applied to determine the spectral noise density of the II-Type SuperLattice photodetector made of InAs/InAsSb.

9

Radiolokacyjny imitator celu

Żygadło Stanisław, Grzywiński Stanisław, Achtenberg Krzysztof

Problemy Techniki Uzbrojenia

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2019

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R. 48, z. 149

75--83

PL

W referacie opisano zaprojektowany i wykonany praktycznie jednokanałowy imitator sygnałów radiolokacyjnych, który pozwala na generację sygnału odbitego od celu o zadanej trajektorii, dla pasma częstotliwości pośredniej. Przedstawione w referacie stanowisko może być wykorzystane do weryfikacji analogowego traktu przetwarzania sygnału radiolokacyjnego na częstotliwości pośredniej oraz algorytmów DSP wykorzystywanych do estymacji współrzędnych imitowanego celu.

EN

The paper describes a single channel imitator for radar signals which was designed and made practically to generate a signal reflected from an aerial target with a given trajectory on the intermediate frequency band. Presented setup can be used to verify the analog channel for radar signal processing at intermediate frequencies and the DSP algorithms used to estimate coordinates of the imitated target.

10

Optical pulse monitoring unit for Free Space Optics

Achtenberg Krzysztof, Mikołajczyk J., Szabra D., Prokopiuk A., Bielecki Z.

Opto-Electronics Review

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2019

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Vol. 27, No. 3

291--297

EN

The paper presents a new construction of an optical pulse amplitude monitoring unit (PAMU) used in a transceiver of Free Space Optics. It consists of a buffer, constant fraction discriminator (CFD), delay line, and a sample and hold (S&H) circuit. In the design FSO system, the PAMU provides to monitor transmitted and received optical pulses with duration of few ns. Using this device, there is no need to apply complicated and expensive digitizing systems. The unique aspect of its construction is to control S&H circuit using the CFD. The lab model of this unit allows to perform tests to define some virtues of constant fraction and leading-edge discriminators. The results were implemented in optical signal monitoring of FSO system. The unit was prepared to cooperate with two different detection modules. Using this setup, it was possible, e.g. to determine operation characteristics of FSO transmitter, identify interruption of transmission, and control light power to provide high safety of work.

11

Peak detection unit for Free-Space-Optics receiver

Achtenberg Krzysztof, Mikołajczyk Janusz, Szabra Dariusz, Prokopiuk Artur, Bielecki Zbigniew

Metrology and Measurement Systems

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2019

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Vol. 26, nr 2

377--385

EN

The paper presents verification of a peak detection method cooperating with infrared radiation detector module applications. The work has been divided into parts including SPICE simulations and presentation of results obtained with the constructed prototype. The design of the peak detector dedicated to applications with very short pulses requires a different approach than that for standard solutions. It is mainly caused due to the ratio of pulse width and time period. In the described application this ratio is less than 10%. The paper shows testing of an analogue circuit which is capable to be inserted in these applications.

12

Wybrane zastosowania układów detekcji promieniowania optycznego w nowoczesnych systemach optoelektronicznych

Mikołajczyk Janusz, Prokopiuk Artur, Szabra Dariusz, Pietrzyk Beata, Nowakowski Mirosław, Achtenberg Krzysztof, Bielecki Zbigniew, Wojtas Jacek

Elektronika : konstrukcje, technologie, zastosowania

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2019

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Vol. 60, nr 1

16--22

PL

Artykuł dotyczy wybranych wyników prac badawczo-rozwojowych realizowanych w Zespole Detekcji Sygnałów Optycznych IOE WAT. Prace te dotyczą głównie fotoodbiorników na różne zakresy widmowe, ultraczułych analizatorów gazów do wykrywania materiałów wybuchowych i biomarkerów chorób w ludzkim oddechu oraz bezpiecznych łączy laserowych w otwartej przestrzeni. W pracy opisano przykładowe układy detekcji promieniowania optycznego z zakresu od ultrafioletu do dalszej podczerwieni, które powstały w ramach prac statutowych i projektów badawczo-rozwojowych. Szczególną uwagę zwrócono na aspekty aplikacyjne uzyskanych wyników wskazując jednocześnie właściwości technologii, dla których zostały one zaprojektowane.

EN

The article presents a brief description of research and development works carried out by Group of Optical Signal Detection at the Institute of Optoelectronics, MUT. These activities mainly concern the construction of photoreceivers operated in various spectral ranges, ultra-sensitive gas analyzers for detection of explosives and diseases biomarkers in human breath, and free space optical data link. Some exemplary detection systems of radiation spectra from ultraviolet to longer infrared, which were designed as a part of academic works or R&D projects, are described. Some practical aspects of these results for some optoelectronic technologies are discussed.

13

System laserowej transmisji danych w otwartej przestrzeni wykorzystujący okno transmisyjne 8-12 µm

Mikołajczyk Janusz, Szabra Dariusz, Prokopiuk Artur, Achtenberg Krzysztof, Wojtas Jacek, Bielecki Zbigniew

Elektronika : konstrukcje, technologie, zastosowania

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2019

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Vol. 60, nr 11

4--8

PL

W pracy przedstawiono analizę właściwości oraz opis konstrukcji laserowego systemu transmisji danych (ang. Free Space Optics – FSO). System ten stanowi unikalne rozwiązanie technologii FSO ze względu na zakres widmowy wykorzystywanego promieniowania, który pracuje w przedziale długości fal 8-12 μm. Opisano również zaimplementowane rozwiązania optomechaniczne, które zwiększyły zakres funkcjonalności tego urządzenia. Przedstawiono wyniki wstępnych badań transmisji sygnałów przy użyciu opracowanych głowic nadawczo- odbiorczych w warunkach rzeczywistych na odległości ok. 800 m. Na podstawie parametrów tych głowic przeprowadzono również analizę zasięgu opracowanego kanału FSO ze szczególnym uwzględnieniem zjawiska scyntylacji. Otrzymane wyniki pokazały, że zaprojektowana głowica nadawczo-odbiorcza może zostać zastosowana do transmisji danych na odległości do 2 km.

EN

The paper presents some performance analysis and description of the design Free Space Optical data link. This link is a unique device due to the used spectral range of radiation – the wavelength of 8-12 μm. The implemented optomechanical designs to increase its functionality were also described. The results of preliminary outdoor tests of the developed FSO transceiver at a distance ca. 800 m are presented. Based on its parameters, an analysis of the data link range in the case of scintillation was also performed. The obtained results showed that the designed FSO transceiver can be used for data transmission at the distances up to 2 km.