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1

Performance analysis of MPPM FSO transmission over Gamma–Chi-square strong atmospheric turbulence

Todorovic Jelena, Spalevic Petar, Panic Stefan, Abdullah Majid Hamid, Pantelic Ivan

Optica Applicata

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2023

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Vol. 53, nr 1

111--126

EN

In this paper, performance analysis of free space optical (FSO) system operating in conditions of strong atmospheric turbulence over Gamma–Chi-square turbulence model, has been carried out. We have observed reception over multi-pulse pulse-position (MPPM) modulation format for the case of strong atmospheric turbulence conditions modeled with Gamma–Chi-square turbulence model and have compared it with turbulence modeling distributions such are: Gamma–Gamma distribution, K-distribution, negative exponential distribution, log–normal distribution. First, we have provided closed-form analytical expressions for average bit error rate (ABER) at the reception for each observed case and then based on them, we have obtained numerical and Monte Carlo simulation results in order to observe turbulence level impact on system performance.

2

Hybrid FSO/mmWave wireless system : a plausible solution for 5G backhaul applications

Isanaka Lakshmi Priya, Meenakshi Murugappa

Opto-Electronics Review

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2022

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Vol. 30, No. 3

art. no. e141950

EN

The explosive rise of wireless services necessitates a network connection with high bandwidth, high performance, low mistakes, and adequate channel capacity. Individual mobile users, as well as residential and business clusters are increasingly using the internet and multimedia services, resulting in massive increases in the internet traffic demand. Over the past decade, internet traffic has grown significantly faster than Moore’s law predicted. The current system is facing significant radio frequency spectrum congestion and is unable to successfully transmit growing amounts of (available) data to end users while keeping acceptable delay values in mind. Free space optics is a viable alternative to the current radio frequency technology. This technology has a few advantages, including fast data speeds, unrestricted bandwidth, and excellent security. Since free space optics is invisible to traffic type and data protocol, it may be quickly reliably and profitably integrated into an existing access network. Despite the undeniable benefits of free space optics technology under excellent channel conditions and its wide range of applications, its broad use is hampered by its low link dependability, especially over long distances, caused by atmospheric turbulenceinduced decay and weather sensitivity. The best plausible solution is to establish a secondary channel link in the GHz frequency range that works in tandem with the primary free space optics link. A hybrid system that combines free space optics and millimeter wave technologies in this research is presented. The combined system offers a definitive backhaul maintenance, by drastically improving the link range and service availability.

3

Performance analysis of a RoFSO link for 5G networks under adverse weather conditions

Jose Tony, Ponraj Narain, John Victor Du

Przegląd Elektrotechniczny

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2021

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R. 97, nr 4

67--69

EN

5G systems are about to be democratized. Radio over Free Space Optics (RoFSO) is a promising technology which could back the rapid deployment of the 5G networks owing to its high data carrying capacity and hazzle free installation capabilities. The RoFSO links use the atmospheric channel for communication and are susceptible to performance degradation due to various environmental factors. In this work, a 26 GHz RoFSO link delivering 10 Gbps is designed and its bit error rate performance is analyzed using Kruze atmospheric model under different climatic conditions like rain, fog, dust, and haze.

PL

Dzięki sieci 5G możliwy jest rozwój takich technologii jak Radio over Free Space Optoics RoFSO. To radio łączy komunikację bezprzewodową z możliwością eliminacji zakłóceń. Opisano system o częstotliwości 26 GHz i przepustowości 10 Gbps.

4

FSO system performance analysis based on novel Gamma–Chi-square irradiance PDF model

Todorović Jelena, Spalević Petar, Panić Stefan, Milosavljević Bojana, Gligorijević Milan

Optica Applicata

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2021

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Vol. 51, nr 3

335--348

EN

In order to provide a novel analytically traceable free space optics (FSO) channel model for describing turbulence based irradiance fluctuations, following basic scintillation theory principles, we have derived closed-form expression for probability density function (PDF) of a new statistical Gamma–Chi-square model. Further, capitalizing on provided model, error performances of FSO system over on-off keying (OOK) transmission scheme both in the presence of atmospheric turbulence and misalignment fading (pointing error) is investigated. For both cases, the average bit error rate (ABER) at the receiving side of the system is determined in an analytically closed form. The results are graphically presented in order to analyze the impact of different levels of turbulence, as well as other relevant parameters, on the quality of the received signal in the OOK modulated FSO system.

5

Comparative BER Analysis of Free Space Optical System Using Wavelength Diversity over Exponentiated Weibull Channel

Shah Dhaval, Joshi Hardik, Kothari Dilipkumar

International Journal of Electronics and Telecommunications

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2021

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Vol. 67, No. 4

665--672

EN

Atmospheric turbulence is considered as major threat to Free Space Optical (FSO) communication as it causes irradiance and phase fluctuations of the transmitted signal which degrade the performance of FSO system. Wavelength diversity is one of the techniques to mitigate these effects. In this paper, the wavelength diversity technique is applied to FSO system to improve the performance under different turbulence conditions which are modeled using Exponentiated Weibull (EW) channel. In this technique, the data was communicated through 1.55 µm, 1.31 µm, and 0.85 µm carrier wavelengths. Optimal Combining (OC) scheme has been considered to receive the signals at receiver. Mathematical equation for average BER is derived for wavelength diversity based FSO system. Results are obtained for the different link length under different turbulence conditions. The obtained average BER results for different turbulence conditions characterized by EW channel is compared with the published result of average BER for different turbulence which is presented by classical channel model. A comparative BER analysis shows that maximum advantage of wavelength diversity technique is obtained when different turbulence conditions are modeled by EW channel.

6

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.

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

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.

9

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.

10

Analysis of Free-Space Optics Development

Mikołajczyk J., Bielecki Z., Bugajski M., Piotrowski J., Wojtas J., Gawron W., Szabra D., Prokopiuk A.

Metrology and Measurement Systems

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2017

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Vol. 24, nr 4

653--674

EN

The article presents state of work in technology of free-space optical communications (Free Space Optics - FSO). Both commercially available optical data links and their further development are described. The main elements and operation limiting factors of FSO systems have been identified. Additionally, analyses of FSO/RF hybrid systems application are included. The main aspects of LasBITer project related to such hybrid technology for security and defence applications are presented.

11

Metoda optycznej transmisji danych z wykorzystaniem laserów impulsowych

Drozd T., Mierczyk Z., Zygmunt M., Wojtanowski J.

Elektronika : konstrukcje, technologie, zastosowania

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2016

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Vol. 57, nr 11

17--21

PL

Aktualnie użytkowane optyczne systemy transmisji danych najczęściej, jako źródła promieniowania wykorzystują lasery pracujące w sposób ciągły. Lasery impulsowe ze względu na impulsowy charakter generowanego promieniowania w systemach transmisji danych praktycznie nie znalazły zastosowania. Ponieważ lasery impulsowe, w zależności od typu mogą generować impulsy o mocy wielokrotnie większej niż lasery CW, zatem bardzo atrakcyjna wydaje się możliwość wykorzystania ich w systemach transmisji danych. W Instytucie Optoelektroniki WAT opracowano metodę transmisji danych wykorzystującą, jako źródło promieniowania półprzewodnikowy laser impulsowy. W artykule przedstawiono opis opracowanej metody transmisji danych oraz analizę możliwej do uzyskania szybkości transmisji. Ponieważ, w celu weryfikacji założeń teoretycznych przedstawionej metody opracowane i wykonane zostały moduły umożliwiające transmisję mowy i danych użytkowych, praca zawiera również opis budowy wykonanych urządzeń oraz wyniki praktycznych testów zestawionego łącza optycznego, w tym badania elementowej stopy błędu oraz badania zasięgowe.

EN

Most of the current optical data transmission systems are based on continuous wave (cw) lasers. It results from the tendency to increase data transmission speed, and from the simplicity in implementation (straightforward modulation). Pulsed lasers, which find many applications in a variety of industrial, medical and military systems, in this field are not common. Depending on the type, pulsed lasers can generate instantaneous power which is many times greater when compared with cw lasers. As such, they seem to be very attractive to be used in data transmission technology, especially due to the potentially larger ranges of transmission, or in adverse atmospheric conditions where low power cw-lasers-based transmission is no longer feasible. It is also a very practical idea to implement data transmission capability in the pulsed laser devices that have been around and already used, increasing the functionality of this type of equipment. At the Institute of Optoelectronics at Military University of Technology, a unique method of data transmission based on pulsed laser radiation has been developed. This method is discussed in the paper in terms of both data transmission speed and transmission range. Additionally, in order to verify the theoretical assumptions, modules for voice and data transmission were developed and practically tested which is also reported, including the measurements of Bit Error Rate (BER) and performance vs. range analysis.

12

Badanie wpływu warunków atmosferycznych na propagację promieniowania optycznego o długościach fal 1,5 µm oraz 10 µm

Garlińska M.

Elektronika : konstrukcje, technologie, zastosowania

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2015

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Vol. 56, nr 8

27-28

PL

W artykule przedstawiono wyniki badań terenowych sytemu łączności optycznej w otwartej przestrzeni. Badania terenowe miały na celu ocenę wpływu warunków atmosferycznych na natężenie odbieranego promieniowania optycznego. Pomiary przeprowadzono dla dwóch łączy optycznych pracujących z długościami fali 1,5 µm i 10 µm. Badania te wykonano w patio budynku przy ul. Kaliskiego 2 w Warszawie, dla odległości między nadajnikiem a odbiornikiem wynoszącej 96 m.

EN

The article presents the results of optical communications system in an open space field researches. These studies were aimed at assess the impact of weather conditions on the strength of the received radiation. Measurements were carried out for two optical links operating with wavelengths of 1.5 µm and 10 µm. These studies were performed in the patio of the building Kaliskiego 2 Street in Warsaw. Obtained distance between the transmitter and the receiver was 96 m.

13

An Overview of Free Space Optics with Quantum Cascade Lasers

Mikołajczyk J.

International Journal of Electronics and Telecommunications

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2014

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Vol. 60, No. 3

259-264

EN

The article presents an overview of the work on quantum cascade lasers application in free space optical systems (Free Space Optics - FSO). There are discussed the main issues of the open-space laser communications and their practical construction. Comparative analyses of each FSO technology were performed. Brief description of quantum cascade (QC) lasers and some developments related to the use of these lasers in optical data link are also presented. In summary, the constructed models of FSO links with QC lasers are characterized.

14

Analiza zasięgowa łączy optycznych

Garlińska M.

Elektronika : konstrukcje, technologie, zastosowania

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2014

|

Vol. 55, nr 8

50-51

PL

W artykule przeprowadzono analizę porównawczą zasięgu laserowych łączy w otwartej przestrzeni (ang. Free Space Optics – FSO). Szczególną uwagę zwrócono na wpływ absorpcji, rozpraszania i turbulencji na propagację promieniowania optycznego o długościach fali 0,8 µm, 1,55 µm oraz 10 µm. Wykazano, że w perspektywicznych systemach FSO pracujących w otwartej przestrzeni mogą być stosowane kwantowe lasery kaskadowe (ang. Quantum Cascade Lasers – QCL) pracujące w zakresie widmowym 8-12 µm. W porównaniu do długości fal stosowanych w komercyjnych systemach FSO promieniowanie to charakteryzuje się mniejszym współczynnikiem absorpcji wynikającym z położenia tzw. okien transmisji atmosfery, mniejszą wrażliwością na turbulencje atmosfery oraz lepszymi właściwościami transmisyjnymi w wypadku ograniczonej widoczności, np. występowania słabych deszczy oraz mgieł.

EN

In this paper a comparative analysis of free space optics links ranges is presented. Particular attention was paid to the impact of absorption, scattering and turbulences on the propagation of optical radiation in the range of 800-900 nm, 1550 nm and 10 microns. It has been proven that in perspective optical systems working in the open space QC lasers operating at wavelength of 10 microns should be applied. They are characterized by a low absorption coefficient resulting from the presence of atmospheric transmission windows and improved transmission properties in the case of limited visibility conditions, such as the weak rain and fog, in comparison with near IR systems. FSO systems operating in the mid infrared range are also less sensitive to atmospheric turbulences.

15

Łącze optyczne z kwantowym laserem kaskadowym

Garlińska M., Mikołajczyk J., Bielecki Z.

Elektronika : konstrukcje, technologie, zastosowania

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2013

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Vol. 54, nr 3

61-63

PL

W artykule omówiono system łączności optycznej w otwartej przestrzeni, pracujący w zakresie widmowym 8...12 µm. Jego głównymi elementami są kwantowy laser kaskadowy (QC) oraz detektor HgCdTe. Wstępne badania łącza dały możliwość oceny wpływu punktu pracy lasera QC na jakość transmisji. Przeprowadzono m.in. pomiary amplitudy sygnału rejestrowanego przez moduł odbiorczy łącza, a także szumów. Określono ich wpływ na poziom elementowej stopy błędów. Uzyskano wyniki, które zostaną uwzględnione w ramach dalszych badań w warunkach terenowych.

EN

This paper presents a free space optical (FSO) communication system operated at the wavelength range of 8...12 microns. The main elements of the system are a quantum cascade laser and MCT photodetector. During laboratory studies, influence of a transmitter operation point on the transission link quality was determined. The obtained results made a possible to define FSO operating point for further system studies in field conditions.

16

Badania wpływu temperatury pracy lasera kaskadowego na jakość transmisji łącza optycznego

Garlińska M., Mikołajczyk J., Nowakowski M., Bielecki Z.

Elektronika : konstrukcje, technologie, zastosowania

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2013

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Vol. 54, nr 10

39-41

PL

W artykule omówiono wpływ temperatury pracy lasera kaskadowego zastosowanego w module nadawczym systemu łączności optycznej w otwartej przestrzeni na parametry impulsu laserowego. Przedstawione łącze pracuje w zakresie widmowym 8-12 µm. Przeprowadzono m.in. pomiary amplitudy sygnału rejestrowanego przez moduł detekcyjny a także wartości skutecznej napięcia szumów w zależności od temperatury pracy lasera i czasu trwania impulsu. W celu oceny jakości impulsu pod kątem transmisji sygnałów cyfrowych przeprowadzono analizę stosunku napięcia sygnału do napięcia szumu dla różnych punktów pracy modułu nadawczego. Uzyskano wyniki, które zostaną uwzględnione w ramach dalszych badań łącza w warunkach terenowych.

EN

The paper presents the impact of quantum cascade laser operating temperature on the parameters of the laser pulse. This laser was applied in a transmitter of free space optical communications system working in the spectral range of 8-12 microns. During experiments, dependance of signal and rms noise value measured at the detection module output, on both the laser operating temperature and pulse duration were was definied. Taking into account data transmission, the signal to noise values for different operating points of the FSO system were analyzed. The obtained results will be useful during further researches under actual working conditions.

17

Analysis of data transmission technique based on pulsed laser

Drozd T., Zygmunt M., Knysak P., Wojtanowski J.

Opto-Electronics Review

|

2012

|

Vol. 20, No. 1

75-78

EN

Pulsed lasers are used mainly in lidar systems as sources of short and highly energetic light pulses. In data transmission systems continuous wave lasers are typically applied, however it is also possible to use pulsed lasers in such systems. Such approach seems to be especially reasonable for devices where a pulsed laser is applied anyway and executes another function (rangefinding). The article discusses a data transmission concept based on a pulsed laser technology. Advantages and limits of such a transmission method are described. Influence of individual transmission elements on the effective data transmission speed is analysed.

18

Compact QCL driver for free-space transmitter

Mikołajczyk J., Garlińska M., Wesołowski M., Wojtas J., Bielecki Z.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2012

|

Vol. 60, nr 4

763-768

EN

The paper presents investigations of a free space optical transmitter operating with quantum cascade lasers. The main goal of the research was to determine influence of lasers driver parameters on an optical data link performance. Using some commercial driving devices, the laser pulse limitations of power, repetition rate and time duration have been observed. In the paper, the preliminary results of the designed laser driver are described. The driver was developed at the Institute of Optoelectronics, MUT in cooperation with scientists from the Faculty Electrical Engineering, WUT. It is characterized by high current efficiency, high pulse repetition rate, and compact construction. Additionally, the driver also includes a controller of Peltier modules

19

Analiza możliwości transmisji danych z wykorzystaniem laserów impulsowych

Drozd T., Zygmunt M., Knysak P., Wojtanowski J.

Biuletyn Wojskowej Akademii Technicznej

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2011

|

Vol. 60, nr 2

63-73

PL

W systemach transmisji danych wykorzystywane są lasery o pracy ciągłej. W artykule przedstawiono koncepcje transmisji danych z wykorzystaniem laserów impulsowych. Jest to szczególnie istotne dla urządzeń, w których laser impulsowy już jest wbudowany i realizuje inne funkcje (np. dalmierz). Przedstawione zostały zalety oraz ograniczenia takiego sposobu kodowania. Dokonana została analiza szybkości transmisji danych wraz z przedstawieniem wpływu poszczególnych elementów kanału transmisyjnego na wynikową szybkość transmisji danych.

EN

Pulsed lasers are used mainly in lidar systems, which generate laser pulses and detect and analyze reflected signals. In data transmission systems, continuous work lasers are used. It is also possible to use pulsed lasers in such systems. These features would be especially important for devices in which pulsed laser is already embedded and execute another function. This article shows data transmission system conception with the use of pulsed laser. Advantages and limits of this transmission method were described. Analysis of speed of data transmission was performed and influence of individual channel transmission elements on the data transmission speed was shown.