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EN
The dynamic development of microelectronics and wireless communication at the turn of the 20th and 21st centuries contributed to the increase in the availability and popularity of all kinds of unmanned platforms, air, land, surface, and underwater. In the case of unmanned aerial vehicles (UAVs), also popularly known as drones, the significant (crucial) advantages are high freedom of motion (i.e., the ability to move in three planes) and the possibility of using it practically anywhere (as opposed to water platforms). These factors influenced the dynamic development of this market sector and the high availability of various models and equipment. UAVs are being used in many sectors and services, both for civil and military purposes. Widespread availability, low cost, and ease of use also favor the possibility of using civilian UAVs for criminal, smuggling, terrorist, or military purposes. Recent armed conflicts, e.g., in Nagorno-Karabakh or Ukraine, and the situation on the eastern Polish-Belarusian border clearly show this. All countries recognize the potential and threat posed by the development of unmanned platforms. Therefore, for several years, special attention has been paid to analyses and research in sensors, effectors, and anti-drone systems. It is worth emphasizing that some effectors (e.g., jammers or spoofers) may significantly affect the navigation process of neighboring objects that use global navigation satellite systems (GNSSs). On the other hand, the use of anti-drone systems is important, especially in the context of protecting institutions and facilities of companies, state administration (i.a., embassies, consulates), army, strategic importance objects (e.g., related to energy, chemical industry), or protection of mass events. In this paper, we present an overview of solutions available on the market and development directions in the field of anti-drone technology.
EN
The recently introduced orthogonal time frequency space modulation (OTFSM) is more robust to large narrow-band Doppler frequency shift than the orthogonal frequency division multiplexing (OFDM), used in the 5G standard. In this paper it is shown how the telecommunication OTFSM-based signal with random padding can be used with success in the 6G standard for detection of high-speed vehicles. Two approaches for detecting targets during the random padded OTFS based transmission are compared in the paper.
PL
Zaproponowana ostatnio modulacja Orthogonal Time Frequency Space (OTFS) jest bardziej odporna na wąskopasmowy efekt Dopplera, niż technika zwielokrotniania z ortogonalnym podziałem częstotliwości (OFDM - Orthogonal Frequency-Division Multiplexing), używana w standardzie 5G. W referacie zaprezentowano jak modulacja OTFS z dodanym sygnałem pilota, w formie losowego przyrostka, może być z sukcesem użyta w standardzie 6G do jednoczesnej transmisji danych oraz do detekcji szybko poruszających się pojazdów. Porównano dwa algorytmy detekcji obiektów, które są możliwe do zastosowania w transmisji RP-OTFS.
PL
W niniejszej pracy przedstawiono wyniki analizy i dekompozycji impulsów radarowych za pomocą metody triangulacji zer spektrogramu w dziedzinie czas-częstotliwość. Sygnał niestacjonarny zaburzony szumem białym charakteryzuje się ściśle określonym rozkładem zer na płaszczyźnie czas-częstotliwość, jeśli do przekształcenia wykorzysta się okno Gaussa oraz krótkoczasową transformację Fouriera (ang. short-time Fourier transform, STFT). Wówczas odległości pomiędzy sąsiadującymi zerami spektrogramu (rozkładu energii STFT) wykazują się inną dystrybucją dla szumu i inną w otoczeniu sygnału. Dzięki tej właściwości możliwe było pokazanie w artykule procesu ekstrakcji impulsów pochodzących z nadajników radiolokacyjnych.
EN
This paper presents the results of the analysis and decomposition of radar pulses using the method of triangulation of spectrogram zeros in the time-frequency domain. A non-stationary signal disturbed by white noise is characterized by a strictly defined distribution of zeros on the time-frequency plane if the Gaussian window and the short-time Fourier transform (STFT) are used for the analysis. Then the distances between adjacent zeros of the spectrogram (STFT energy distribution) are characterized by a different distribution for noise and in the signal vicinity. Thanks to this property, the article shows the process of extracting pulses from radar transmitters.
PL
Artykuł zawiera analizę porównawczą statystycznych i niestatystycznych metod estymacji macierz kowariancji zakłóceń w przestrzenno-czasowym adaptacyjnym przetwarzaniu (ang. Space-Time Adaptive Processing STAP) sygnału radarowego dla modelu radaru MIMO (ang. Multiple Input Multiple Output). Zaprezentowano istotę, przebieg algorytmu STAP oraz właściwości najnowszych typów metod estymacji macierzy kowariancji zakłóceń. Autorzy przytoczyli w artykule również swój wkład w rozwój tej technologii.
EN
The article presents a comparative analysis of statistical and non-statistical methods of estimating the clutter covariance matrix in Space-Time Adaptive Processing by using Multiple Input Multiple Output radar geometry. In addition, the properties and stages of the STAP algorithm are presented, as well as the main features of the latest methods for estimating the clutter covariance matrix. Moreover, the authors referenced their contributions to the development of this technology in the article.
EN
The paper presents an analysis of the accuracy of determination of parameters of the position of aircraft using data from the AVIA-W radar. In the first place, the authors determined the position of the aircraft as well as the range and azimuth parameters by the AVIA-W radar, located in Dęblin. This was followed by a determination of the absolute position error of the aircraft and the determination of the range and azimuth measurement error by the AVIA-W radar. The research test was carried out using a Diamond DA40 NG aircraft on which a GPS satellite receiver was mounted in order to determine the flight reference position. In addition, the range and azimuth measurements for the aircraft were acquired from the AVIA-W radar. Navigational calculations were conducted for polar and rectangular planar coordinates. Based on the performed research, the azimuth error was found to be -1.4°, while the radar range measurement error was equal to -0.04 km. The conducted research is experimental in its character. In the future it will be repeated and extended to the GCA-2000 radar, which is also located at Dęblin military airfield.
PL
W pracy przedstawiono analizę dokładności wyznaczenia parametrów pozycji statku powietrznego z użyciem danych z radaru AVIA-W. W pierwszej kolejności dokonano wyznaczenia pozycji statku powietrznego oraz określenia parametru zasięgu i azymutu przez radar AVIA-W, zlokalizowany w Dęblinie. Następnie dokonano wyznaczenia błędu absolutnego pozycji statku powietrznego oraz określenia błędu pomiaru zasięgu i azymutu przez radar AVIA-W. Test badawczy przeprowadzono z użyciem samolotu Diamond DA40 NG, na pokładzie którego zamontowano odbiornik satelitarny GPS w celu wyznaczenia pozycji odniesienia lotu. Dodatkowo z radaru AVIA-W pozyskano pomiary zasięgu i azymutu do statku powietrznego. Obliczenia nawigacyjne zrealizowano dla współrzędnych biegunowych i prostokątnych płaskich. Na podstawie wykonanych badań stwierdzono, że błąd azymutu wynosi -1,4°, z kolei błąd pomiaru zasięgu radaru wynosi -0,04 km. Przeprowadzone badania mają charakter eksperymentalny i w przyszłości zostaną powtórzone i rozszerzone o radar GCA-2000, który także znajduje się na lotnisku wojskowym Dęblin.
EN
This paper presents an analysis of the accuracy of aircraft positioning using radar and GPS satellite data. In particular, this study shows the results of research on determining the position of an aircraft, as well as the range and azimuth parameters for the GCA-2000 radar to the GPS solution. The research used measurement data from the GCA-2000 radar and the Thales MobileMapper Pro receiver placed onboard a Diamond DA-40NG aircraft. The flight experiment was carried out at the EPDE military airport in Dęblin. It was found that the average error in determining the position of the aircraft for the GCA-2000 radar was 295.57 m. Moreover, the average error in determining the range for the GCA-2000 radar is 138.12 m. Additionally, the average error in determining the azimuth for the GCA-2000 radar is equal to 0.408°.
EN
In this paper, we consider the possibility of using the radar characteristics of precipitation in order to reduce the negative impact of the echo signal generated by them on the radar tracking of objects performed by the ship’s radar. In the formation of an echo signal by precipitation, both the precipitation particles themselves: their size, state (solid or liquid phase), shape, and the factors that determine their combined action (concentration, relative position, preferred orientation), are important. The size of rain particles when compared to the wavelength emitted by the ship's radar antenna contributes to the creation of a larger or smaller noise echo on the display of the ship's radar, the power of which in the Rayleigh scattering region toward the radar is characterized by the effective scattering area. Falling raindrops are a collection of randomly located reflectors and their scattering properties depend on the spatial distribution and regularity of movement. At the same time, the radar characteristics of clouds with precipitation generated by them can be used in ship radars to determine the intensity of the atmospheric process along the ship’s route, and the uncertainty in determining the attenuation of the power of an electromagnetic wave emitted by a ship’s radar antenna and passing through the precipitation zone can be reduced by simultaneous use of two wavelengths on which ship’s radars operate.
EN
The article presents the description, assumptions and subsequent steps of the space-time adaptive processing (STAP) algorithms used as a signal processing tool in radars. The possibilities of object detection using the Sample Matrix Inversion (SMI) and Data Domain Least Squares (DDLS) algorithms were compared and showned. The article shows the impact of the use of parallel programming on the computation time of both algorithms. The main aim of this study was to propose an efficient method for the real-time implementation of the STAP algorithm in airborne radar systems. The idea of using parallel programming in STAP, supported only by the preliminary research results presented above, gives a real chance for the casual implementation of the STAP algorithm in a radar operating in close to real time mode.
PL
W artykule przedstawiono opis, założenia i kolejne kroki algorytmów przestrzenno-czasowego przetwarzania adaptacyjnego (STAP) stosowanych jako narzędzie przetwarzania sygnałów w radarach. Porównano i pokazano możliwości wykrywania obiektów za pomocą algorytmów Sample Matrix Inversion (SMI) i Data Domain Least Squares (DDLS). W artykule przedstawiono wpływ zastosowania programowania równoległego na czas obliczeń obu algorytmów. Głównym celem pracy było zaproponowanie efektywnej metody implementacji algorytmu STAP w czasie rzeczywistym w pokładowych systemach radarowych
9
Content available Derecho radar analysis of August 11, 2017
EN
This paper presents an analysis of the derecho phenomenon that occurred over Poland on August 11, 2017. The storm caused 6 fatalities, 39 injuries (Mańczak et al. 2022), and some of the greatest damage in the history of Polish forestry. Our study is based on radar meteorology and measurements from the Polish POLRAD radar network, and intended for advanced meteorologists with good knowledge of radar measurements. The research used both standard and specialized radar products as well as classic and Doppler scan data. The Doppler velocity products were especially useful for showing the characteristics of the storm. The analysis was mainly based on data from two radars: Poznań and Gdańsk, but the composite maps, consisting of data from more than one radar, were also analyzed. The derecho complex developed from unorganized thunderstorm cells over SW Poland and moved toward the NE. The various stages of the evolution of the system are presented and analyzed, accounting for the formation of a SC, the development of a rear inflow jet (RIJ), the split of the entire system, and the appearance of the bow echo signature. Significant factors affecting the scale of the wind damage were: (1) the extensive mesocyclone which evolved to the mesoscale convective vortex (MCV), and (2) a strong rear flank downdraft interacting with the rear inflow jet (RIJ).
EN
The aim of the article "Research and comparative analysis of the accuracy in determining the parameters of the position of aircraft by air traffic control radars Avia-W and GCA-2000" is to test the difference in determining the parameters of the position of aircraft objects by radars used at Dęblin airfield. In particular, the paper presents the results of positioning accuracy, azimuth and distance accuracy for two radars: GCA-2000 and Avia-W.
PL
Celem pracy „Badanie i analiza porównawcza dokładności określania parametrów położenia statku powietrznego przez radary kontroli ruchu lotniczego Avia-W oraz GCA-2000” jest zbadanie różnicy określania parametrów położenia obiektów powietrznych przez radary używane na lotnisku w Dęblinie. W szczególności w pracy pokazano wyniki dokładności wyznaczenia pozycji, dokładności pomiaru azymutu i odległości dla dwóch radarów GCA-2000 i Avia-W.
EN
The Electronic Chart Display and Information System (ECDIS) became the central navigational tool on modern ships. The system comprises numerous navigational and other components, each of them with its limitations and reliability. Due to ECDIS's revolutionary features, navigators are tempted to place excessive reliance on the system. Such reliance on it as a sole navigational aid is undoubtedly a problematic issue. The proposed paper is a segment of a systematically carried out research among ECDIS stakeholders. ECDIS EHO (Experience, Handling, and Opinion) research aims through research activities based on a user-centred approach to develop and improve the educational framework. The overreliance on the ECDIS system motivated the proposed research, which focused on system users' opinions and practice regarding confirmation of the accuracy of information displayed on ECDIS, particularly concerning positional sensors. Analysis of answers collected by the ECDIS EHO questionnaire represents a backbone of the research supported by previous achievements. The answers have been categorized and discussed, revealing certain worrying aspects referring to the system's positional error experienced by users. Furthermore, preferred methods of cross-checking ECDIS information have been identified and have differed among respondents based on their rank on board. Additionally, answers indicate certain doubts between users’ interpretation of the best confirmation method and the actual selection of the used method. The importance of cross-checking navigational data in avoiding overreliance and maintaining situational awareness has been presented in the conclusion chapter and the proposal for further work.
EN
During warfare and acts of terrorism an extreme threat to vehicles and other high-value assets comes from armour-piercing projectiles. Under these conditions, defence systems should include devices capable of rapid detection of these threats. Defence assets should also be provided with counter-projectile systems capable of destroying incoming armour-piercing projectiles at a safe distance from the asset to be protected. This paper describes the concept of a system comprising of a lightweight short-range radar and a counter-projectile for countering armour-piercing projectiles. The purpose of the radar is to monitor the environment and search for incoming armour-piercing projectiles. When an armour-piercing projectile is detected in a designated monitoring area, an automatic command is given for the counter-projectile launcher to be fired. The counter-projectile deployed can be equipped with a single or multi-sensor detection head unit and an explosive payload module, both being the primary components of the warhead. When the signal analysis blocks interfaced with the detection head determine that the armour-piercing projectile to be struck down is in the target position in relation to the counter-projectile deployed, they automatically command the explosive payload module to detonate. The components of the system concept were tested in proving ground conditions. The successful results of these tests confirmed the validity of the solutions initially adopted and the execution of the individual systems.
PL
W działaniach bojowych oraz podczas aktów terrorystycznych bardzo dużym zagrożeniem dla pojazdów i innych ważnych obiektów są ataki przy użyciu pocisków przeciwpancernych. W takich warunkach systemy obrony powinny dysponować, między innymi, urządzeniami zdolnymi do szybkiego wykrycia zbliżającego się zagrożenia. Systemy obrony powinny być wyposażone również w antypociski mogące zniszczyć nadlatujący pocisk przeciwpancerny w bezpiecznej odległości od chronionego obiektu. W pracy opisano koncepcję zestawu składającego się z lekkiego radaru bliskiego zasięgu oraz antypocisku do zwalczania pocisków przeciwpancernych. Zadaniem radaru jest obserwacja przestrzeni i poszukiwanie atakujących pocisków przeciwpancernych. Gdy wykryty pocisk przeciwpancerny znajdzie się w przewidzianej strefie wówczas automatycznie zostaje wydana komenda do odpalenia antypocisku. Wystrzelony antypocisk może być wyposażony, między innymi, w jedno- lub wielo-sensorową głowicę detekcyjną oraz moduł wybuchowy będące głównymi elementami głowicy bojowej. W chwili, gdy bloki analizy sygnałów współpracujące z głowicą detekcyjną stwierdzą, iż zwalczany pocisk przeciwpancerny znalazł się w zakładanym położeniu względem antypocisku, wówczas automatycznie wydają komendę do detonacji modułu wybuchowego. Elementy koncepcji zestawu zostały zbadane w warunkach poligonowych. Pomyślne wyniki tych badań potwierdziły poprawność wstępnie przyjętych rozwiązań oraz wykonania poszczególnych układów.
13
Content available Mobility of Radars on the Today’s Battlefield
EN
In this article the author makes an attempt to characterize the main factor – mobility – which is to be taken into consideration while designing the ground radar component (passive and active radars) of the Air Defense systems in order to enable them to operate on the contemporary battlefield. He presents the latest theoretical views on the relationship between the usage of anti-radiation missiles and the mobility of the passive and active radars as the key ability to protect them against such weapons. In particular the author emphasizes that the anti-radiation missiles present nowadays the biggest threat for the effective Air Defense systems, which are today characterized by a high complexity degree. He also stresses the need to combine the radars, both passive and active, into one system allowing for the streamlining of their work parameters and thus ensuring their complex usage. The gaining of those capabilities shall guarantee that the parameters of the air surveillance radar area can be defined effectively.
14
Content available A Review on Impulse RADAR
EN
RADAR plays a vital role in military applications since its origin in the 2nd world war. Recently it has been used in surface inception, health monitoring, infrastructure health monitoring, etc. In these applications, Ultra-wideband RADAR systems are more popular than traditional RADAR systems. Impulse RADAR is a special kind of ultra-wideband RADAR, which is mostly used for surface penetration, through-wall imaging, antimissile detection, anti-stealth technology, etc. because of its high resolution and low center frequency. Out of all these applications, impulse RADAR has been used intensively as a ground-penetrating RADAR for the detection of land mines, underlying pipelines, buried objects, etc. This report has attempted to provide the steps for designing the impulse ground penetrating RADAR (GPR) as well as provides the value of crucial parameters required in the design process of commercial GPR systems.
EN
This article presents a calculation of condition detection wind farm by ship’s radar. The authors used computer programme CARPET 2 for simulation different propagation condition. Wind farm echoes are visible in significant distance and can be advantage to ship position mark.
EN
The reception antenna diagram side lobe’s level suppression algorithm for marine radar by means of antenna array with only a few tuning elements of antenna array is considered. The others no tuning elements of array are choosing for obtain a given value of average side lobe level suppression and with given value of antenna directivity without using of numerical optimization procedures. Special algorithm of interaction of these no tuning elements for realizing Supperdirectivity properties is used. The structural diagram of array is presented. The efficiency of suggested design has been investigated.
EN
In this article, the author will try to explain the basic principles of the practical focus of using radar in maritime navigation, analysing its potential errors and limitations. An attempt will also be made to describe the basic seamanship practice of how to set up the radar, determine the radar blind sectors, calculate the radar position accuracy, generate a basic anti-collision radar report, calculate CPA, TCA, BCR, BCT etc., and verify the effectiveness of a trial anti-collision manoeuvre by using the radar in the different radar modes when navigating in restricted sea areas.
PL
W dobie dynamicznego rozwoju sprzedaży omnikanałowej menedżerom odpowiedzialnym za intralogistykę coraz trudniej w sposób odpowiedzialny udzielić odpowiedzi na pytania zarządów firm, które oczekują zwiększenia efektywności działań. Jakie będą faktyczne korzyści z zakupu i wdrożenia nowej technologii? Jak można zmierzyć efektywność danego rozwiązania? Jak określić jego stabilność? Jakie koszty instalacji i konserwacji firma musi ponieść?
EN
This article applies radar interferometry technologies implemented in the ENVI SARscape and SNAP software environment provided by the processing of data from the Sentinel-1 satellite. The study was carried out based on six radar images of Sentinel-1A and Sentinel -1B taken from September 2017 until February 2018 with an interval of one month and on the radar-module of the already mentioned SNAP software. The main input data for solving the considered problem are radar images received from the satellite Sentinel-1B on the territory of Stebnyk-Truskavets for six months with an interval of one month. Monitoring of the Earth’s surface using radar data of the Sentinel-1A with a synthesized aperture is implemented with the application of interferometric methods of Persistent Scatterers and Small baselines interferometry for estimating small displacements of the Earth’s surface and structures. The obtained quantitative and qualitative indicators of monitoring do not answer the processes that take place and lead to vertical displacements the six months but do provide an opportunity to assess the extent and trends of their development. The specification in each case can be accomplished by ground methods, which greatly simplify the search for sites with critical parameters of vertical displacements which can have negative consequences and lead to an emergency.
PL
W artykule przedstawiona została implementacja systemu detekcji naruszenia strefy chronionej z wykorzystaniem urządzenia typu SDR (ang. Software Defined Radio – radio definiowane programowo). W publikacji opisano proces projektowania toru przetwarzania, uwarunkowania implementacyjne wnoszone przez parametry urządzenia SDR oraz wyniki symulacji i testów rzeczywistych systemu.
EN
This paper describes implementation of protected zone violation detector in a Software Defined Radio (SDR) equipment. Parameters determination and processing path designing, considering device-originated restrictions, were described, followed by simulation and real in-hardware test results.
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