This PDF file contains the front matter associated with SPIE Proceedings Volume 11055, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.

Simulative generation of images that would be registered by a photo camera installed on board UAV is a complex process, consisting of a number of geometric transformations and image processing operations. The article presents a method of creating such images based on the assumed UAV navigation parameters, i.e. geographical coordinates, altitude and angles of orientation. The operation of the proposed simulator is based on the use of equations related to the geometry of the perspective photo and the principle of operation of a digital camera. The simulator may be used as a generator of testing images, especially for research works related to creating and developing algorithms for vision-based navigation. It allows to simulate and save images for the whole preprogrammed flight trajectory. It supports also creating robust algorithms for processing erroneous data from integrated navigation systems. Comparing images obtained from an onboard camera with their simulated counterparts allows to determine synchronization errors, which is important for the appropriate operation of a vision-based navigation system.

The paper shows initial experimental results of research works taken by teams of the Institute of Electronic Materials Technology and Military University of Technology aimed at manufacturing in Poland photoconductive semiconductor switches (PCSSs) on semi-insulating (SI) gallium phosphide (GaP) wafers. These devices will allow pulsed switching of power circuits to high-voltage networks as well as triggering the high-energy of electromagnetic radiation. The properties and concentrations of deep-level defects, contributing to the charge compensation enabling the SI GaP crystals to be obtained, have been studied by the high-resolution photoinduced transient spectroscopy (HRPITS). The chips of switches with two planar electrodes separated by a gap of 2 mm were made and the connections enabling the dark current and photocurrent measurements as a function of the electric field strength to be carried out were assembled. The ways of increasing the switch amperage in the conductive state are discussed.

The article presents the results of research related to the echoes cancellation in the hydroacoustic channel using cepstral methods. The effectiveness of tested methods was evaluated basis on a comparison of the estimation of hydroacoustic channel’s impulse response determined for measured signals before and after echoes cancellation. The paper presents simulation tests and result of experiments carried out in laboratory conditions and in the real environment.

The article presents a set of parameters used to compare the quality of synthetic aperture radar terrain images. This quality can be assessed using qualitative and quantitative indicators. Quantitative parameters include: spatial resolution, peak-sidelobe ratio (PSLR), integrated sidelobe ratio (ISLR), image contrast and its entropy. The quality of radar images is commonly evaluated by studying signals reflected from quasi-point objects (e.g. corner reflectors) located inside the imaged area. The radar image of such an object consists of a main lobe and side lobes that can be considered in the azimuthal and range direction. Therefore, spatial resolution, PSLR and ISLR can be determined separately for the azimuth and range. However, geometric distortions are usually analyzed in a qualitative way.

Military wireless communication systems provide services using radio transmission technologies. However, this technology is exposed to modern radio-electronic warfare devices. In some operational scenarios, an application of laser data link (Free Space Optics - FSO) makes it possible to increase data transmission reliability and security. Such capability could be obtain using so-called hybrid FSO/RF communication system. The development of optoelectronic devices (lasers and photodetectors) operated in the spectral range of 8 – 12 μm (Long Wavelength Infrared Radiation - LWIR) enabled to construct a new FSO link. Compared to currently used FSO systems operating in 700-900 nm (NIR) or 1300 – 1550 nm (SWIR) spectral ranges, this link is characterized by less sensitivity to atmospheric phenomena (fog, mists or turbulences) and by greater difficulty of detection. The performed analyses shown that the use of FSO/RF technology systems can provide increase in data transmission security, link availability, secretiveness of operation, and immunity to intentional interference. The paper presents virtues of some wireless communication technologies based on radio, optical and hybrid system configuration. The status of the research on FSO link operated at LWIR wavelength range is also described. This study has been performed in the frame of LasBITer project financed by The Polish National Center of Research and Development. The developed optical data link is a unique device in relation to the FSO technologies available today, because of its operation in LWIR spectrum using quantum cascade lasers and HgCdTe detectors. Scenario of FSO/RF data link works in military operation is also presented.

Modern systems of radio communication planning have two aims: ensuring both internal and external compatibility of the system (i.e. avoiding both interference within the network and jamming or interference by other sources). Currently, systems of planning concentrate only on ensuring internal compatibility of the radio system and avoiding usual interference from external sources. The part of ensuring external compatibility of the radio system related to avoiding jamming was carried out by using appropriate mode of radios, ex. frequency hopping mode, free channel search mode, etc. With this approach, we had no information about efficiency of the methods used. In particular, we had no information whether we have made the radio nets immune to jamming. We present a model of planning frequency assignment by a mobile military communication network taking into account not only internal interference of planner's own system but also potential presence of a rational opponent.

To do this, we use dynamic games with incomplete information and the concepts of belief distorted Nash equilibria, both in deterministic and stochastic form of expectations. This analysis allows us to find remedies to several types of behaviour of the opponent. From theoretical point of view, in existing approaches, the problems of frequency assignment for a mobile military communication network in various time instants are treated as independent static optimization problems with only one decision maker. First of all, we have to be conscious, that we face not a simple optimization problem, but a game: besides our communication network, there may be an opponent, whose aim is to detect and/or jam our transmission. Besides, a dynamic character of interaction has to be taken into account: using a plan of frequencies defined a priori and switching to the same reserve plans in predetermined way whenever jamming appears, makes it possible for the counteracting unit of the opponent to uncover the rules of our behaviour. Using dynamic game theory, in particular dynamic games with incomplete information, allows us to utilize information about rules of behaviour of the opponent during the process of frequency planning. The side which takes the dynamic character of the decision making problem into account as the first can benefit from this fact.

Synchronization in wireless networks based on OFDM modulation has a huge influence for proper receiver operation. Comparing available techniques used for synchronization purposes, authors propose modification of well-known Schmidl and Cox algorithm through matched filter implementation instead of standard correlator. This solution allows precise detection of the OFDM symbol beginning. Influence of CFO on preamble length as well as different types of coefficients usage methods are investigated in last chapter of the article.

Koshelev antenna is a device with a complex structure: it is an traveling-wave antenna, an electrical monopole and a loop antenna. The antenna is intended for the radiation of short pulses of high power and rise time up to several picoseconds. The design of the antenna is briefly described in the literature; in particular, it is not known how the construction parameters of the antenna affect its basic purpose. The article discusses the operation of a single Koshelev antenna and a system consisting of several such antennas with narrow-band excitation. It shows how the radiation changes in the case of a system of several identical elements. It seems that the array of the same elements can radiate a lobe with an angle of several degrees only.

The paper presents a novel method for NLFM radar signal instantaneous frequency estimation. Up to now there are only a few limited reports in this field. The method involves combined short-time Fourier transform and IF curve smoothing in time – frequency plane. The algorithm performs a fine estimation of instantaneous frequency of noise buried signals up to -3 dB. Due to FFT and simple filtering application, there is no high computational load needed. Simulation results indicate that the algorithm is robust and outperforms well-known phase differentiation method.

The paper discusses the state of the art of ground penetrating radars operating with continuous wave. Principle of operation, basic architectures and main construction problems are also presented.

The article presents a short description of the methods of shielding terrestrial objects using land jammers. The necessary mathematical formulae needed to calculate the effectiveness of radar jamming to shield a single ground object for two variants are given: when the jammer is near to the shielded object and when it is away from it at a fixed distance. For the energy criterion, the method for calculating the sector of the ground object shield was presented, according to the parameters of the jammer, jammed airborne radar and aircraft flight altitude. The necessary mathematical relations have been given to determine the sector of the object's shield. The angular relations and distances between the object to be covered, the jammers and the attacking aircraft change during the raid. The results of numerical calculations illustrating the presented method for the exemplary parameters of the jammer station, the radar and the variant of the air raid are presented in the respective tables and diagram. The implementation of an effective object shield of the facility using land-based jammers depends mainly on the exact knowledge of the technical parameters of the jammed radars (the emitter database), the jammers, the distance between them and the attacking aircraft, the degradation coefficient used for calculations, the electromagnetic wave propagation conditions and the used jamming method. In order to achieve high effectiveness of on-board radars jamming, the software supporting the decision making process depends on the dynamically changing battle scenarios.

The article presents a method of recognizing sources of electromagnetic signal emission on the basis of signals generated by using deep neural networks. These signals are measured in electronic recognition receivers, processed into a digital signal and then undergo recognition. The main purpose of the article is to present software which, based on the detected signal, is to recognize it. The software can also be used as a subsystem in Electronic Intelligence (ELINT) devices, including detection of radiolocation systems, jammers, recognition of aircrafts, ships, vehicles based on the signal shape of radar cross section (RCS) and subsequently comparison them to the emitter database (EDB). The implementation of this system is presented in a simulation environment and with the help of a signal generator that has the ability to make changes in signal signatures earlier recognized, calculated and written in database. The proposed software allows to examine a significant number of different signals. The article contains a description of components of software, such as signal base, learning subsystem and signal generator. The results of the system operation are presented in the form of screenshots from individual software components. The speed of software operation, the effectiveness of recognition systems using artificial neural networks is presented by means of tables and appropriate illustrations. Also presented is the problem of learning the neural networks at the GPUs (graphics processing units) and the way of choice the learning coefficients.

The strategy of secure communication originating from the NNEC (NATO network Enabled Capability) concept assumes the use of effective and safe transport mechanisms at various levels of the heterogonous C2 (Command and Control) NATO systems. SCIP (Secure Communication Interoperability Protocol) is the basic solution introduced by NATO for secure communication of different network devices through networks with restricted bandwidth. SCIP technology is designed to provide interoperable end-to-end connectivity in a variety of communication systems, from military radio communication, traditional telephone communication system through satellite communication channels to VoIP and various types of mobile telephony standards. It is designed to operate at the application layer with minimal dependency on the characteristics of the lower layers. The implementation of the SCIP protocol in various devices requires the unification of transmission and signaling procedures as well as the methods of coding the speech signal. Therefore, the main challenge associated with this issue is the provision of high security, high availability and high quality of service (QoS). The implementation of any encryption algorithm in nowadays heterogenous networks with restricted bandwidth can lead to degradation of the voice quality due to increased loss packets and packet latency. This paper will investigate how the end-to-end SCIP encryption impacts on QoS of voice communication. The quality of voice call is assessed in terms of lost packet ratio, latency and jitter with and without SCIP algorithm. Research is performed using the MultiDSLA tester and PESQ and POLQA methods. The results of laboratory tests indicate what effect SCIP encryption-based security has on the voice call quality.

The article presents the concept of how to use convolutional networks as a method for processing digital images acquired in visible region of light for the needs of smoke detection in large open area. The meaning and consequences of massive blaze were underlined on the basis of statistical data concerning the forest fires. The proposal to overcome the difficulties in using traditional methods for detection of fire threat by image processing techniques was discussed. The idea, inner structure and properties of a convolutional neural network as a tool for automatic feature generation and image recognition were presented. The algorithms of data processing used in vision systems for fire detection were analyzed including the solutions implementing the networks. On the basis of the analysis the proposal to develop a neural network for smoke detection with the use of the strategy called transfer learning was presented. Using the image base of fires available on the web, the quantified assessment of the proposed approach was conducted. In the research the AlexNet framework was adopted to recognize smoke in images. The processing of the net was illustrated with examples of activations of selected layers when fed with images containing smoke. The 99% sensitivity reached by the proposed processing together with the 1% of false alarm rate seems to be very promising for the system of fire surveillance based on watchtowers or air vessels monitoring large open areas.

The rapid development of sophisticated military command and control systems causes the dynamic demand for broadband services including the transmission of video in real time by using telecommunications links. One way to resolve the problem of limited bandwidth in used military wireless systems is to use modern broadband radio stations. Broadband radio stations in addition to undoubted advantages such as increased system bandwidth, have also some limitations – in comparison to narrowband radios, broadband radios offer a smaller range and work in a wide band and high transmitter activity associated with the generation of maintenance traffic, which makes it easier to detect radio emission by the opponent. Modern electronic warfare systems can track down such systems and overpower them. That is why one of the main tasks, which currently are facing designers of advanced broadband radio communication systems, is to develop mechanisms to immunize broadband radio stations on the targeted interference. In this article the method of implementation of the national waveform allowing for securing the transmission in broadband radio stations will be presented. Transmission modes of the radio station (TDMA, CSMA/SC, CSMA/MC) will be discussed considering advantages and disadvantages of each of the above-mentioned modes of operation. In the next chapter selected results of experimental studies of broadband radio station R-450C with the above-mentioned implemented operating modes and universal defeat device for generation of diverse broadband interference will be presented. The obtained results will allow to assess the implemented modes of radio stations for resistances of broadband radio communication system on selected targeted interference. The developed analysis and obtained measurement results may be helpful both for people organizing radio communication using broadband radios as well as for those responsible for the proper operation of electronic warfare systems.

Currently, high-power electromagnetic pulses are detected through antennas with conductive elements, which can causing the measured wave to interfere with waves reflected from metal elements. Moreover, they are characterized by a strongly non-linear frequency nature. Additional measuring system elements, such as a balun, attenuators, a limiter, which also impact the transmittance of the entire system are also used frequently. Appropriate selection of attenuation values when testing electromagnetic signals with unknown parameters is also problematic. An important aspect is also ensuring adequate detector resistance to the impact of high-power electromagnetic pulses. The paper discusses the test results for a prototype optoelectronic transducer based on the Faraday effect. The detector is designed in the fully dielectric technology. The system enables detecting a magnetic component of an electromagnetic field. Very similar amplitude values and signal shapes were obtained during the first tests involving the recording of system responses upon harmonic excitations with selected frequencies. The transfer characteristics for selected optical signal wavelengths (660 nm and 880 nm) were also measured, and a system response upon magnetic field pulse excitation was also recorded. Based on the measurements taken when determining the transfer characteristics, the linear correlation coefficients for a system operating at various optical light wavelengths were calculated. The incidence results also showed the need to conduct further studies in terms of increasing the sensitivity of the constructed detector. The disturbance level on the detector output should also be limited.

The article presents experimental research indicating that the impulse response of the communication channel, determined in practice, are not of an universal character, but only represent its approximate value for the frequency on which this measurement was made. Phases for each of the replicas of the measurement signal were determined during the analysis of the received signals in the basic band. Phase changes of individual replicas of the signal as a function of changes in the position of one of the measuring antennas are presented. The coherence bandwidth and the coherence time of the channel were determined. The tests were carried out in urban environment in static conditions and when antennas were moving.

One of the main concerns of the institutions dealing with the spectrum management as well as persons responsible for radio networks planning is the lack of electromagnetic resources. This is caused by various reasons. On the one hand, there is a very rapid increase in the number of radios used in modern military platforms. Another factor connected with it is the fact that modern radio communications systems, in order to meet the users’ requirements, e.g. to be able to transmit video streaming in a real time, need wideband transmission channels. On the other hand, current static methods cause substantially suboptimal spectrum management. An average level of the spectrum resources utilization in a frequency band from 30 MHz to 2000 MHz very rarely exceeds 15%. Contemporary tools for frequency planning use so called Interference Conflict Margin (ICM). It is a measure of the protection against interference from potentially disrupting transmitter at receiver side. But ICM do not take into account features of the modern radios which have anti-interference mechanisms implemented. Since modern radios adjust modulation and coding schemes to the current state of the radio channel, these features should be taken into account. The same applies to the range of the network and level of power necessary to maintain communications. In this point, the protection criterion should be defined similarly to the protection ratio in ITU-R BT.1368, ITU-R P.372-9 documents. Another important factor is to take into account the way how considered radio network works. Is there only voice communications or data? In the second case, it is also important to determine the minimum transmission rate. In this paper a more flexible approach is presented. Adaptive modulation and coding schemes as well as power levels are taken into account. Presented results of experiments and simulations show benefits arising from proposed approach.

The paper presents the results of experiments that allow to determine the validity of use of the Automatic Speaker Recognition (ASR) in devices that register voice signal via throat microphones. Throat microphones are used in extremely difficult registration conditions, e.g. in tank headsets, therefore high efficiency of identification of speakers obtained for such a device allows to significantly extend the range of applications of ASR. The presented research results are complemented with results of speakers identification tests carried out using a traditional electret microphone on the same population of voices, which allows for unequivocal comparison of the impact of an acoustic channel on operation of ASR. The paper also includes a brief description of operation of the automatic speaker recognition system based on a cepstral analysis of a voice signal and Gaussian Mixture Models (GMM).

An important problem that persons responsible for radio communication systems face is how to make these systems immune to jamming. Rapid development of contemporary electronic warfare systems is a reason why that task is difficult to solve without special supporting tools to analyze wave propagation. Currently, an attempt to jam an enemy radio network is a multiphase process for which the most crucially important is collection of information on the enemy radio communication system and then processing it. The results of the analysis enable to estimate efficiency of intended jamming activity and make the decision on emission of jamming signals. The tools that are useful for estimation of the possibility to jam selected radio objects are wave propagation prediction models chosen earlier in the phase of operational and technical analysis. A good example of propagation prediction model of HF waves is the model based on ITU-R P.533-13 recommendation. It is distributed as a free of charge dynamic linked library P533.dll.

The article presents the proposal of implementing the P533.dll library in order to increase the effectiveness of HF radio communication systems jamming. The information in this article may be useful for those who deal with HF radio communication and for those responsible for the operation of electronic warfare systems.

The problem of spectrum management is relevant both for civilian and military systems, but it is much more complex when coalition operations are considered. Some limitations to efficient data exchange over radio channels are caused by the static frequency assignment method, inefficient frequency usage and lack of a common spectrum operational picture in NATO coalition operations.

These problems could not be solved at the national level, thus it was of high importance to take up the discussion and to make a NATO-coordinated effort. For this purpose NATO has established the Research Task Group on Electromagnetic Environment Situational Awareness (NATO IST-146 RTG-069) aiming to work out the concept of the Radio Environment Maps (REM) enabling their users to obtain the spectrum operational picture and to minimize the level of interferences between wireless systems of coalition forces. One of the main goals of the research group is to define the architecture of the system and to specify interfaces to other systems in the area of frequency planning and constant spectrum monitoring. It is assumed that the function of the sensors may be performed by dedicated radio receivers, spectrum analysers, cognitive radios and Electronic Warfare (EW) or Intelligence, Surveillance, Reconnaissance (ISR) systems.

In the paper we discuss the concept of the REM and the problem of the data delivery from other systems, e.g. EW systems equipped with a variety of sensors. We also present exemplary maps created using different methods and analyze how the deployment of sensors affects the quality of maps.

The construction of electrical machines that are used as surge generators with high power pulse values is discussed the in paper. A structural and mathematical model of a synchronous surge generator is described. The course of the current function in a three-phase short-circuit condition is presented and analysed. The construction parameters of a machine of this type in terms of maximizing the signal power are discussed. A special structure of the machine armature slot-tooth zone is an attribute of synchronous surge generators. This applies to minimizing any reactance of the machine’s electrical circuits. It is also important to protect the generator-exciting winding against the effect of the armature impact while generating power pulses.

Direction finding that is establishing an angle position of microwave sources is an important element of reconnaissance of electromagnetic space and threat warning tasks. For these purposes, direction finding of sources, which are operating transiently and irregularly is especially significant, as well as difficult to accomplish. In these cases, the direction of the emission source is established on the basis of a single pulse, using the phase method or the amplitude method. The precision of direction finding for a single microwave emitter is relatively good. It may not exceed a tenth of a degree over the wide frequency range. In operating conditions, where strong disturbances exist, for instance with several sources operating simultaneously, results of direction finding may have a significant error. Ideas of monopulse direction finding using amplitude methods and phase methods were described in the work. Results of simulation for a single microwave emitter, as well as multiple emitters operating simultaneously were presented. It was shown that when multiple sources operate at the same time, the direction finding process becomes interrupted, but an intra-pulse analysis of received signals enables reduction of the error of angle position measurement of each observed emitters.

Research work related to the design and use of anti-radiation missiles (ARM), and any systems intended to protect radar and other radiation-emitting installations against ARMs, requires access to theoretical and physical models of direction finding devices, which are used in guidance systems installed in the aforementioned missiles. In this work, the authors present the concept of an electromagnetic source seeker working in the microwave band. In the solution presented herein, the direction finding is accomplished using the phase method. Phase analysis of signals emitted by the observed microwave source is relatively fast due to the quadrature configuration of the microwave phase discriminator used for this purpose. During an attack, an anti-radiation missile moves at great speed, which exceeds 1000 m/s. Due to this fact, the missile needs to be equipped with systems, which are capable of estimating the direction of the targeted source, and which can update the relevant information as quickly as possible. Such properties in the presented concept were achieved by using comparators with analogue inputs and logical digital (0/1) outputs. As a result, the information from the direction finding channel is obtained in a digital format, with the number of bits (the resolution) being dependent on the number of applied comparators. The authors therefore assume that a coarse direction finding will be used when the deviation between missile trajectory and the direction of target source is relatively large, whereas the more precise target location estimation algorithm will be used when the trajectory of the missile is matched (within established limits) to the direction of the emission source.

The article contains an analysis of potential prospects of simultaneous localization and mapping (SLAM) algorithms application in imagery intelligence (IMINT). The first part of the paper presents a detailed description of the SLAM problem. Diverse solutions to the simultaneous localization and mapping problem and related research over the years are presented. The most promising of SLAM approaches are pointed out. To facilitate SLAM analysis, the problem is partitioned into three parts. First, various SLAM estimation techniques are characterized. A mathematical theory behind the usage of parametric filters, non-parametric filters, and least squares method is presented. Further, differences between SLAM algorithms are described in terms of various sensors used on-board SLAM platforms for the examination of the environment. The examination is commonly addressed as landmark extraction. A separate part of the paper discusses the image processing in SLAM. The last part of the SLAM analysis is dedicated to various approaches to map presentation. Further, the properties of SLAM techniques are characterized in terms of their potential benefits to IMINT. Prospects of increased efficiency, accuracy and safety of intelligence gathering process are discussed.

One of the most important aspects in contemporary alliance and coalition communication is to ensure an adequate level of security for data and voice transmission. Continuous technological development is a factor that significantly hinders the development of the coalition standard aimed at protecting real-time data transmission (audio and video) in a reliable and safe way. For a long period of time, the coalition nations encountered problems connected with establishing a correct transmission between national systems. In order to achieve interoperability of communication systems, the United States government has made available and presented the standard FNBDT (Future Narrowband Digital Terminal) which in the course of time took the name SCIP (Secure Communication Interoperability Protocol). This protocol is being developed to this day by working groups consisting of representatives of scientific institutions and companies from the armed industry of NATO countries. Thanks to international cooperation the Protocol was adopted as standard STANAG 5068. It allows the use of cryptographic mechanisms to block the transmission of voice and data in a standardized way, ensuring interoperability of existing and newly formed allied and coalition communication systems for voice transmission. The SCIP protocol is based on two speech codecs: MELPe and G.729D. The article will discuss the current work carried out in NATO working groups on the definition of the COMSEC function and the way it is implemented in broadband radio stations to develop a broadband waveform for coalition activities. Also, the national waveform to secure communication in the broadband radio station will be presented. In the next chapter there will be the presentation of selected experimental results of broadband radio R-450C with the above-mentioned implemented mechanisms to protect voice communication. The obtained results will allow to evaluate the implemented mechanisms in terms of security. The developed analysis and obtained measurement results may be helpful both for people organizing radio communication using broadband radios as well as for those responsible for the proper operation of electronic warfare systems.

This paper presents a method of conflicts removal in fusion of identification (attribute) information provided by ELINT – ESM sensors (Electronic Intelligence – Electronic Support Measures). In the first section, the basic taxonomy of attribute identification is adopted in accordance with the standards of STANAG 1241 ed. 5 and STANAG 1241 ed. 6 (draft). These standards provide the following basic values of the attribute identifications: FRIEND, HOSTILE, NEUTRAL, UNKNOWN and additional values: ASSUMED FRIEND and SUSPECT. The last values can be interpreted as a conjunction of basic values. The basis of theoretical considerations is the Dezert-Smarandache theory (DSmT) of inference. The paper presents and practically uses for combining identification information from different ELINT – ESM sensors four information fusion rules proposed by the DSmT - the Proportional Conflict Redistribution rules (PCR1, PCR3,Pcr4 and PCR5).In the next section, rules of determining attribute information by ESM sensor equipped with the data base of radar emitters are presented. It was proposed that each signal vector sent by the ELINTESM sensor contained an extension specifying a randomized identification declaration (hypothesis). This declaration specifies the reliability of the identification information - basic belief assignment (bba) for the identification information set. Results of the PCR rules of sensor information combining for different scenarios of radio-electronic situation (deterministic and Monte Carlo) are presented in the final part of the paper. At the end of the paper conclusions are given. They confirm the legitimacy of the use of the Dezert-Smarandache theory into information fusion and its proportional conflict redistribution rules for ELINT-ESM sensors.

The PSO (Particle Swarm Optimization) algorithm uses a population of single particles, randomly distributed over the function search space, in order to construct an optimal flight path. During the algorithm iteration execution, each particle evaluates its fitness function according to the actual position. Then, every particle moves towards a direction dependent on its actual best position and the position of the best particle so far. The procedure ends when the iteration limit is reached or fitness criterium is met. In the presented autonomous UAV 3D path planning method, a PSO algorithm is used to build a feasible path, optimized in terms of fuel and threat cost. The process begins when the UAV detects or receives information about threats appearing on its primary trajectory. The population of particles moves in the search space of three variables, which are the angles of pitch, roll and yaw. These angles determine the spatial orientation of the UAV, indicating its direction of movement in each step. Further waypoints are chosen with consideration of the distance to the target and violation of threat areas. As a final result, the PSO algorithm constructs a suboptimal, feasible path which could be used as a reference trajectory for the UAV’s automatic control system. Simulation results turned out to be completely repeatable and indistinguishable, despite the stochastic nature of the algorithm, which proves its great optimization abilities. Moreover, its short execution time (within seconds) allows this procedure to be used in real time applications.

The protection of critical infrastructure objects such as airports, sea ports or border crossings is one of the essential security problems. In order to perform this task an electromagnetic emission passive monitoring method may be used. This is realized with distributed passive wideband radio frequency (RF) sensors utilizing the time difference of arrival (TDoA) method of electromagnetic emission source location. The complexity of the algorithms implemented in such systems requires high computational power of the signal and data processing systems. This implies the need for computational complexity reduction of implemented algorithms. In this article a computationally efficient algorithm for cross-correlation of received signals in time difference of arrival method is presented.

Infrared image recognition by means of FLIR cameras (forward-looking infrared) is one of the elements of the recognition of the maritime situation and it supports in many situations the creation of so-called maritime picture. This paper presents results of two FLIR image classifiers research. The first part presents the use of neural networks to classify images of maritime objects, while the second part presents the classifier using the time series comparison method called the DTW (data time warping). The neural network is a three-layered artificial neural network (feed forward). Both classifiers use the histograms of vertical projection of pre-processed FLIR images as input data. These histograms are created as a result of FLIR color images processing, including, among others, transformation of color images into grayscale images, grayscale images segmentation using the Otsu algorithm, rescaling, centering and leveling. In the final part of the paper preliminary test results of the both classification methods for a set of maritime objects FLIR images registered in the Baltic Sea are presented.

This paper presents the analysis of chosen localization algorithms for radio electronic radiation sources. Analysis of the accuracy of the location estimation of AOA, TDOA and FDOA (SDF) algorithms was made by examining the resistance of algorithms to the location error of the sensors and the effect of geometric blur on the accuracy of the location of the radiation source. The simulations were carried out in the MATLAB environment. The paper presents the results of discussed numerical analysis.

Single-function microwave frequency detectors are used in the structures of multichannel frequency discriminators. They allow determining the frequency of an unknown signal in a very short time of the order of hundreds of nanoseconds. The shape of the output voltage of the single-function detector versus frequency is described with a cosine or a sine function. In the systems, where a great accuracy of frequency determination is not required, and a time measurement is vital, it is possible to apply only one single-function frequency detector. A single-function frequency detector is composed of two blocks: a system of developing of proportional phase difference and a phase sensitive detector. The function of the first block is to generate two output microwave signals with a phase difference between them proportional to the frequency of the input signal. A phase sensitive detector converts the difference of phases of input signals into voltage. The output voltage is subject to further processing and, based on it, the frequency of the input signal is determined.

Today’s solutions of reconnaissance and electronic warfare systems require high accuracy in determining the location of the recognized object. It also involves the need to track the trajectory of the object's movement with particular attention to maneuvers and direction changes. The article presents a tracking simulation study of a land object carried out in MATLAB environment for generated various types of trajectories. For each case, the values of root mean square and relative errors are determined. These errors, as well as the evaluation of graphical imaging, allow to assess the usefulness of implemented tracking algorithms using nonlinear Kalman’s filtration.

In the next stage, measurements were taken in real terms using a system built from four stationary ultra-wideband (UWB) modules and one mobile built-in land vehicle. The measurement data contained both the raw distance data and the locations obtained from the system tracking application. At this stage, preliminary verification of the designed tracking algorithms was carried out using raw distance data between the modules and the object to create own tracking application. The results of the above operations for different trajectories are presented in the form of appropriate graphical imagery. They confirm the possibility to track the trajectory of a land object using distance measurement from ultra-wideband modules based on the own implemented algorithms. The determination of location is made with high accuracy while improving parameters in relation to factory algorithms at the time of maneuver.

This paper presents a method of recognition of maritime objects based on FLIR (forward looking infra-red) sensor images using two methods: Principal Component Analysis (PCA) and Dynamic Time Warping (DTW). A combination of the Principal Component Analysis PCA with the eigenimages analysis method reduces the dimensionality of the recognition problem. DTW method finds the shortest distance between two time series allowing a transformation of time for both compared series. In the presented maritime objects FLIR images classifier the DTW method is used to compare the vertical brightness projection histograms of silhouettes for the recognized object and the object pattern. To determine the silhouette of a maritime object the Otsu thresholding algorithm is used. The paper describes the eigenimages method, the DTW method of comparing time series and the data fusion method combining conclusions both classifiers. In the final part of the paper are presented preliminary test results of the classification method for a set of maritime objects FLIR images registered in the Baltic Sea.

Information superiority requires constant recognition of operational spaces because modern command and control need information flow from sensors to effectors. Such approach requires access to services for mobile users. Moreover, the sensors become a part of the radio network, too. Currently, armed forces are providing troops with personal radios. This requires more frequencies available for the radio networks to operate, which means that an electromagnetic warfare starts at the lowest level of an echelon. A traditional frequency access becomes inefficient. A dynamic spectrum access is believed to increase capability of frequency usage. A dynamic spectrum access implementation needs cognitive radios which can monitor the spectrum. The cognitive radio uses information about the spectrum to prepare a plan of action in case of some interference. A knowledge about current situation within the cyberspace could also be used by other systems (e.g. electromagnetic warfare system). The article presents the capability of cognitive radios and highlights advantages resulting from a connection between radio and electromagnetic warfare systems. The paper emphasises certain risks associated with a lack of connection between radio communications and electromagnetic warfare systems.

The concept, work principle and analysis results for signal distribution networks of planar antenna arrays with reflection parameters improvement using shunt-stubs have been presented in the paper. Signal distribution network is the important part of every antenna array and lets to split input signal to every radiating element. 1-dimention arrays fed parallelly, from basic 2-elements, to complex multielement structures were analyzed. Numerical analysis results, confirmed by real structure measurement results have been presented. Antenna arrays with rectangular, as the most popular radiator shape were taken under tests. Authors propose new approach in using of shunt-stubs. In traditional approach, shunt-stubs are often used to single patch impedance correction. The signal distribution network, as a part of antenna array, is the source of additional susceptances and impedance mismatching in consequence. In multielement arrays this adverse influence should be compensated or corrected. The using of shunt-stubs not only at patches, but in every signal splitting stage is proposed by authors. Additional stubs at every T-junction do not complicate of overall circuit and carry significant contribution in matching. Additional elements does not influence in overall size in array configurations majority. A few simple antenna arrays, working in 2,4 GHz Wi-Fi band were manufactured and measured. Measurement results confirm equity of stubs applying.

The subject of study were low resolution SAR imagery, provided by Sentinel 1A and 1B, which can be obtained using open sources. Due to the great interest of products, an analysis of the interpretation possibilities of imaging acquired in interferometric wide swath mode and extra wide swath mode were made. Before exploring the possibilities, the proposed methods have been tested to improve the quality of radar images. Depending on the analyst’s needs as well as the polarization channel used, adaptive filters such as Frost, Lee-Sigma, and in some cases Gamma-Map are recommended. However, the use of classification and pseudocolor allows dividing the area of interest into basic fields, such as the urbanized area, water or vegetation. Satisfactory results were also obtained by integrating different polarization bands. The impact of incidence angle of radar beam on photographing the object was also shown.

Satellite imagery obtained from open sources intelligence is of great importance for the security of the state, as the data obtained allow monitoring the location and activity of troops, as well as detecting and identifying objects and military equipment. The evaluation of the quality of these data is an important factor in their practical use. In the world literature, many authors considered the problem of image quality in terms of the spatial resolution assessment, but in this article the research concerned determination of the imagery interpretability and its improvement. The article presents the methods of evaluations and qualitative analysis of reconnaissance imagery. The analysis were carried out both by subjective and objective methods, in order to optimize the individual approach of specialists to the problem being addressed. The subjective assessment method consisted in the visual analysis of the views, which were detailed in the NIIRS. The objective evaluation was made based on the calculation of the metrics characterizing the spectral and spatial quality of the imagery. In addition, the influence of various signal processing methods was studied to improve the quality and potential of image interpretation. Radiometric amplification operations, context transformations and pansharpening were applied. The conducted research work have allowed the development of the concept of methods for improving the image quality, which resulted in their better interpretation. The use of signal processing methods (mainly radiometric amplification and high-pass filtration) resulted in improved image quality in the assessment based on both mathematical indicators and the NIIRS.

The nature of wireless network transmission means that an attacker does not have to be in the place where such a network is deployed. It is possible to sense, capture and analyze network traffic from a distance without being detected. If the network is not well secured, discovering of the information is not a problem. Security is one of the major concerns regarding Wi-Fi other than performance or range. Security should be one of the primary factors to consider when planning a wireless network. However, a lot of people who use it or intend to use it are not aware of the problem. Dictionaries with passwords, fake access points (AP) or backdoors in the routers’ software are just some of the methods used by attackers. Recently, a lot of methods have been related to socio-technical activities. In such cases, even secure systems can be vulnerable, because the target of the attackers is not focused around a technical feature but on people’s behaviors. This is a case, because, “human factor” is very often the weakest element in the security chain. Therefore, the aim of this paper is to raise the security awareness of users and protect wireless networks against adversary attacks. Particular attention is paid to the severity, possible targets as well as defense strategies against intruder’s actions. In this context, new WPA3 protocol promises to make it harder to break the into a Wi-Fi network. The article also presents a discussion on new features of WPA3 and their impact on improving the security of Wi-Fi networks.

Kubara Lamina is working on the development of a new type of pulsed-power magnetron with megawatts output power operating in the L-band. An important part of the design work are computer simulations of electromagnetic interactions with an electric charge. In order to get the most reliable results, the task was carried out with the help of specialized calculation software from two independent producers - CST Studio Suite and MAGIC Tool Suite. The results obtained with the help of both programs were similar, but there were differences between them resulting from the specific features of the software. The differences concerned the time needed to create an electron spokes in the interaction area between the cathode and anode of the tube as well as the threshold voltage at which the generation of high frequency oscillation began. On the basis of numerical simulations, the optimal geometrical dimensions of individual details were obtained and the magnetron prototype was created. The tube was subjected to laboratory tests under dynamic conditions. To ensure proper input power parameters, a dedicated impulse modulator powered from supercapacitors batteries was constructed. The energy of the electromagnetic wave generated during the dynamic operation of the device was absorbed in the waveguide ended with high power load. The test results obtained under the experimental conditions allowed to verify the structure of the model designed using simulation software. Tests in the available power range of the power supply confirmed very good compatibility of the tube parameters with the results of electromagnetic simulations. An additional advantage of carrying out the simulation was the shortening of the design process, because the first model of the device already worked in accordance with the technical assumptions.

The paper presents the results of the development of a method and an algorithm for the synthesis of optimal basic signalcode structures in the form of code binary sequences, with a minimum criterion for the side lobes of the periodic autocorrelation function of the indicated sequences. To develop this method, approaches based on set theory and number theory were used. The method is based on a discrete representation of the periodic autocorrelation function of sequences in the form of a system of equations defined on a set of integers, set-theoretic interpretation of the constituent parts of sequences, their integer transformations, mutual properties and relations. A number of transformations of the constituent parts of the sequences are developed, analytical expressions for the dependence of the sum modulus of the sequence elements on the sum of the side lobe levels of their periodic autocorrelation function are derived, and the necessary conditions for the existence of sequences are defined and formulated. The relationship between the parameters of the code binary sequence and the canonical representation of the Euler function on the dimension of the sequence is determined. Analytical relationships between the levels of the side lobes of the periodic autocorrelation function and the parameters of the transformed sequence structures are obtained. The criterion of the effectiveness of the developed method and the corresponding algorithm is the ratio of the number of all possible variants of code binary sequences of a given dimension to a quantity that is determined by the developed algorithm; an expression was obtained to estimate the indicated amount. This efficiency is confirmed by the results of simulation and experimental research. The developed method can be used for the creation of secretive noise-proof data transmission radio systems, remote control systems, radar, and communications.

On a freeway, a sudden stop of a vehicle poses serious threat to all the road users in the following vehicles and it often leads to accidents. Due to high speed and intensity of the traffic, in such situations multiple crashes often occur. The detection of a stopped vehicle on a freeway and possibly early warning of the other drivers, that they should lower their speed and maintain caution may contribute to decreasing of the number and limiting the consequences of car crashes. In the article a structure of a system for traffic on a freeway monitoring and an algorithm allowing for detection of stopped vehicles in such system are presented.

The Polish Land Forces (PLF) are equipped with diagnostic-repair shelters (pol. AD-R) designated to conduct the diagnostic test and repair of telecommunication devices. Surprisingly, there is lack of similar solutions when it comes to contemporary Electronic Warfare (EW) systems, which are equipped with specific devices. On ad-hoc basis this lack of capabilities can be compensated for with diagnostic and repair post of the AD-R shelter, designated for conducting diagnostic tests and repairs of radio devices that are in use in the PLF. However, available measurement equipment does not fully cover the frequency range and power levels typical for contemporary EW systems.

Some improvement on this situation may be brought about by a new project aimed at designing a modernized AD-R shelter, named ADR-K. This shelter will have a wider range of measurement capabilities in relation to frequency ranges and generated power levels. However, the diagnostic equipment of this shelter will make it possible to perform only basic tests of the devices applied in EW systems which are used by the PLF. Neither extensive tests of these devices nor diagnostics of EW equipment used by the Navy or the Air Forces are possible.

In the paper we discuss the needs for the diagnostic tests of devices used in typical subsystems of the EW system. We present the capability of the Military Communication Institute in the area of test-checks and calibration of direction finders. Finally, we characterize the capabilities of AD-R and ADR-K shelters in relation to typical EW system and their equipment.

In military radars a special attention is paid to fast moving targets and the ballistic objects. Detection, identification and tracking of such objects is a critical task in air surveillance radars, artillery radars and C-RAM systems. The development of algorithms that realize this aim requires testing many potential radiolocation situations. Preliminary tests can be realized using a software simulator of air picture generated by a radar. This article presents a simulator that is capable of generating the plots accordingly to the simulated radar’s operating mode and its operational parameters. The objects modeled in the simulator are among the others the ones with the ballistic trajectory. Except the objects’ plots there are generated the plots that result from false alarms. Every simulated plot contains the information about position (range, azimuth and elevation) and the value of the echo signal amplitude at the output of the detector. The principles of operation of the particular parts of simulator and selected results are presented.

Wireless local area networks (WLANs) are a cost-efficient solution that satisfy most current communication requirements in domestic, public and business scenarios. However, WLANs face two main challenges. Firstly, they must address dense scenarios, which is motivated by the continuous deployment of new access points to cover new areas. Secondly, the current evolution of services toward real-time high-definition audio and video content significantly increase users’ throughput needs. This paper includes a new Wireless LAN amendment to IEEE 802.11 specification. The new amendment is named IEEE 802.11ax (also High Efficiency WLAN) and increases the per-user throughput by 4 times compared to existing WLAN standards. This is to enable to operate a large number of devices (laptops, smartphones and Internet of Things equipment) producing a lot of data. This article overviews some of new PHY and MAC enhancements and describes the potential benefits and drawbacks of each one. The comparison with its predecessor IEEE 802.11ac is carried out. Because the proposed solution is still not ratified, the article focuses on the open issues and provide a description of the mechanisms.

FH emissions are currently used in many wireless communication systems, where military communication is a special area of their application. The use of such emissions reduces the likelihood of detection and interception of transmission and increases their resistance to jamming. The larger is the set of carrier frequencies, the more FH emission is dispersed and harder to detect and disrupt. Currently used frequency allocation algorithm does not allow sharing of available frequencies in the same area. For this reason, the number of assigned frequencies for individual network drops significantly, reducing all the advantages of FH emissions. In this paper an effective way to use frequency resources to increase the capacity of the transmission channel assuming a certain number of radio networks or the certain number of available carrier frequencies is proposed. The basic assumption is the possibility of simultaneous operation of many FH radio networks in the same territorial area, on a common frequency set. At a certain probability of collision, the dependence of the number of radio networks which worked simultaneously, from the cardinality of a common set of carrier frequencies and the influence of the number of frequencies on this probability is considered. The results of the analysis of the number of collisions between different FH networks working simultaneously in the same area with an identical set of carrier frequencies are also presented. Relevant mathematical formulas are proposed for different collision scenarios that can be used in the frequency assignment process. The results are verified in practice with the use of VHF radios.

Due to the dynamic growth of applying civilian and military unmanned aerial platforms, a large saturation of the airspace with this type of objects is observed. There are many problems associated with this, among which there are the following: lack of systems informing about the location of other flying objects and violations of protected areas by unauthorized flying platforms. In this paper the concept of direction finding and localization of radio emissions using the Unmanned Aerial Vehicles based on the idea of a hierarchical “swarm” is presented. It is also discussed the UAV detection methods taking into account the specific features of detected radio signal and selected aspects related to the functioning of UAS. Geolocation techniques are presented and one of them, dedicated to direction finding sources of radio emissions, is indicated as preferred. Additionally, relevant mathematical formulas for geolocation method are proposed.

The report examines the issue of increasing the efficiency of detecting complex impulse stochastic signals in the process of their generation against the background of quasi-periodic deterministic interference by using wavelet transformations and neural networks. An example the detection of a triple-wave stochastic signal is considered. One of the most characteristic signs of the shape of such signals is a sharply expressed asymmetry: the amplitude of the negative part of the signal is usually 3-4 times higher than the positive maximum amplitude. The second very important feature is the ratio of the positive parts amplitudes of the signal: the amplitude of the right-hand side is always greater, or in extreme cases, equal to the amplitude of the left-hand side. The proposed technique for processing such impulse signals against a background of quasi-periodic interference by using wavelet-neural technologies for analyzing digital signals. For this purpose, an artificial neural network was constructed, which made it possible to detect such signals at the beginning of their development, starting from a signal-to-noise ratio of 1.5 times, which is twice as good as the threshold for visual analysis. The proposed technique can be used in the analysis of pulsed signals in radar systems, mobile railroad rail diagnostic systems by the Magnitodynamic method, as well as in the experimental work of processing digital stochastic signals of various objects, when it is necessary to observe the dynamics of the signal change.

In the paper output signals of adaptive beamformer of a land-based AESA (Active Electronically Scanned Array) [14] surveillance radar were analysed for simulated air picture. Obtained results were compared with those achieved from classical beamforming technique used typically with little ambient interference, in fully customisable parameters of environment and simulated object. Received data was processed by a monopulse based angle estimator. Selected methods of adaptive beamforming techniques were analysed and classified by their ability to improve signal-tointerference ratio in a given scenario for ABT (Air-Breathing Threats) objects. Obtained results were confronted with expected deformations in main lobe of antenna directional pattern and their effect on accuracy of estimated angle. Object’s parameters calculated using adaptive beamforming techniques were compared with those received when no improvement of signal-to-interference ratio technique was used. The possibility of applying multiple (adaptive) monopulse ratio curves for multiple antenna patterns in manual, automatic or semi-automatic mode was investigated.

In contemporary devices, reconnaissance systems, and radio-electronic warfare there is a necessity to process very large amounts of measurement data in real time. For this purpose, the possibility of hardware implementation for various types of algorithms in FPGA (Field-Programmable Gate Array) is of great importance. With the intensive development of semiconductor technology observed in the recent years, programmable devices have undergone very significant changes in recent years. A notable increase in logical resources has enabled implementation of a programmable processor core in the FPGA.

This paper presents an example of the system which is capable of processing measurement data obtained from a radar as well as control data required for controlling the processing circuit which has been implemented in MicroBlaze processor. The MicroBlaze processor is a soft processor designed for the effective implementation within programmable systems. In this paper two solutions based on the Xilkernel real time system (a solution based on Linux) and the Xilinx Standalone version have been discussed. The proposed solutions may be the basis for building efficient data processing components in WRE devices. Performance tests of the individual solutions have been made on the basis of signals received from the FMCW (Frequency-Modulated Continuous-Wave) radar.

Modern military operations are increasingly conducted in urban areas. Therefore, in the upcoming communication and radio-electronics systems, it is important to allow for the propagation phenomena characteristic for these areas and to mitigate their effects. The direction-finding systems used in localization procedures for emission sources are particularly susceptible to multipath propagation. Analyzes available in the literature show that the urbanized environment contributes to the increase in dispersion of the signal reception angle, which negatively affects the accuracy of bearing methods. If the localized emission source is equipped with a directional antenna then the angular spread is strictly dependent on the width and direction of the antenna beam, which directly affects the accuracy of the tracking system. This paper presents a parameter impact analysis of the emission source antenna, environment, and spatial conditions on the bearing system location error. The presented analysis is based on simulation studies carried out using a multielliptical propagation model. The geometric structure basis of this model is the power delay profile (PDP), which represents the transmission properties of the propagation environment. In this case, PDPs based on the standard 3GPP model are used. The presented simulation results and accuracy evaluation methodology of the bearing systems can be the basis for the method development for minimizing location errors in such systems.

The article presents the process of creating an example multi-domain Software Defined Network based on open source solutions. Significant threats to the SDN and currently used protection practices were discussed. Authors proposed a solution to the problem of resource authorization and authentication by introducing a Hidden Data Layer based on steganographic methods to SDN. Hidden Data Layer consists of three essential elements, i.e. a Head Resident which doubles the functions of a public SDN controller and is a superior unit concerning public one, a Hidden Layer Protocol realising communication between individual network elements. The third element is Hidden Protocol Interpreter as an interpretive and executive function which carries out tasks sent by secret layer protocol. This type of solution assures at first fast and effective detection of threats and secondarily redundancy of the control layer in the case of disabling or debilitating the use of the public controller.

There are more and more steganographic techniques used in IP networks. Modification of packet headers of different protocols, frame bit-breaking or delay-packet delay control is just a few examples used in network steganography. Technological development determines the emergence of new, more advanced methods of secretive transmission. The increase in the popularity of the Software Defined Network (SDN) creates the opportunity to develop a completely new, robust against attacks and transparent for traffic analyzers, the way of traffic management based on hidden communication channels. This article contains a proposal for a Hidden Data Layer (HDL) mechanism in SDN networks. The concept consists in introducing the so-called Head Resident (HR), who oversees the operation of the traditional SDN controller. Terminal devices equipped with Hidden Protocol Interpreters (HPIs), after prior authorization by HR, transmit important data via a hidden data channel. HR will collect and record data sent through a hidden data channel, and if it detects an anomaly in the network operation, it responds appropriately (e.g. by disconnecting a network device or taking control over the operation of the entire network). Such architecture allows you to transmit sensitive data in a universally available network in multi-domain architecture in a robust and reliable way.