Electromagnetic interference detection method to increase the immunity of a microcontroller-based system in a complex electromagnetic environment

In order to improve the fidelity and controllable of electromagnetic environment(EME) building, and build realistic EME for testing and researching the complex EME effect on the electronic information systems, this paper puts forward Equivalent building methods of complex EME based on the meta-elements. First, the paper analysis the domestic and foreign research which presents the current situation and the demand, and then puts forward the methods and expounds the core idea of basing the meta-elements to realize the equivalent EME building. Further it introduces extraction method of the electromagnetic signal environment meta-elements, and builds the description of them. In the end, it put forward the method and process to build the complex EME based on the meta-elements. This research results provide the technical support to improve the level of test EME building.

To accurately evaluate Beidou(BD) receivers complex electromagnetic environment adaptive capacity, based on the analysis of the working mechanism and the easy attack of the receiver, BD receiver facing war complex electromagnetic environment is constructed, simulation on the effect of signal capture and tracking is carried out, and assessment method is studied. The relationship between the positioning success rate and communication success rate of a certain type of BD receiver and electromagnetic environment complexity is given, providing BD receiver application with important reference significance.

Electrical stimulation vs thermal effects in a complex electromagnetic environment

The complex geographical environment and electromagnetic interference environment within the radar deployment position area will seriously degrade the radar detection performance. Focusing on the urgent requirement of optimizing radar deployment in complex geographic and electromagnetic environments, the environment-constrained radar position positioning optimization method is investigated. Firstly, based on the terrain and electromagnetic interference environment of radar positions, a radar position selection method under both geographic and electromagnetic environment constraints is established. Then the propagation loss under complex geographical terrain is calculated by combining the radar equations, and the detection power of target height layer and the coverage power of the focused area are used as the evaluation indicators for the superiority of radar sites. Finally, the detection range of the radar under multiple environmental constraints is visualized. The problem of complex radar operational scenarios in real systems and the single constraint considered in traditional radar equipment deployment methods is addressed. By calculating the propagation loss, terrain loss, electromagnetic loss under multiple environmental and electromagnetic constraints, and adding actual elevation and terrain data as reference, a more realistic and objective analysis of the impact of the environment around the position on the performance of radar equipment is provided, and finally the evaluation indexes and selection methods is proposed in this paper. The proposed evaluation indexes and selection methods and visualization can provide accurate, reliable and intuitive strategies for optimizing the deployment of radar equipment under multiple constraints.

Radar signal sorting is a key technology in electronic warfare. The quality of signal sorting directly determines the outcome of electronic warfare. The accuracy and real-time performance of signal sorting are two important indicators to evaluate the quality of signal sorting. With the increasingly complex electronic countermeasure environment, there are many radar radiation sources in the battlefield, and the signal aliasing is serious. At the same time, there may be pulse loss and interference pulse in the electromagnetic environment. In such a complex electromagnetic environment, in order to improve the accuracy and real-time of radar signal sorting and master the battlefield initiative, this paper proposes a method of radar signal batch processing sorting based on sliding window. Firstly, the radar signal sorting transient library and the sorted radar signal library are set up, and the transient library is used to store radar signals in the sliding window. Move the sliding window continuously from the starting point. When the number of signals in the transient library is higher than the specified threshold, sort the radar signals in the transient library, and then store the sorted radar signals in the sorted radar signal library and delete them from the transient library. When the sliding window moves to the end point, the signals in the sorted radar signal library are merged. Simulation results show that compared with traditional methods, the proposed method has higher sorting accuracy and better real-time performance when there are more radar pulses and pulse loss.

Frequency hopping (FH) communication has good anti-fading, anti-jamming and anti-eavesdropping capabilities, so it is one of the main ways to combat electronic jamming. In order to further improve the anti-jamming capability of FH communication, the parameters such as fixed frequency interval, hopping rate and hopping frequency in conventional FH can be assigned with time-varying characteristics. In order to set appropriate hopping parameters to improve the performance of the system in the electromagnetic environment with various types of jamming, a heuristically accelerated Q-learning (HAQL) method is proposed in this paper. Firstly, a theoretical model for the parameter decision-making of FH system is made, and the key parameters affecting the energy efficiency of the system are analyzed. Secondly, a Q-learning model in complex electromagnetic environment is proposed, which includes setting states, actions and rewards, as well as a HAQL-based decision-making algorithm is put forward. Lastly, simulations are carried out under different jamming environments, and simulation results show that the average energy efficiency of HAQL algorithm is higher than that of the SARSA algorithm, the e-greedy QL algorithm and the HQL-OSGM algorithm, respectively.

Fishtail divertor (FTD), a new divertor concept, is a significant research object of EAST tokamak divertor system. Considering the requirement of sinusoidal current precision and stable output with variable frequency (10-3800Hz) and adjustable amplitude (0-5000A) in complex and arguable electromagnetic environment, a resonant frequency feedback control strategy is proposed for FTD magnet coil power supply. The equivalent mathematical model of the FTD coil PS and control process is set up. Through detailed theoretical analysis and simulation, the conclusion of performance optimization based on control strategy is obtained. At the work of frequency feedback control strategy, the power supply can promptly identify the resonant network frequency deviation caused by the interference of electromagnetic environment on the equivalent load characteristics within 1.5S, and actively correct the excitation voltage frequency, so as to ensure the accuracy of the FTD magnet coil current. Finally, the correctness of the design is verified through experimental tests.

Modern warfare is carried out in a complex electromagnetic environment, where noise suppression interference directly affects the detection ability of airborne warning radar to target, in order to make airborne warning radar play its due role in battlefield. More and more requirements are put forward for radar combat capability in complex electromagnetic environment, that is, the requirement of radar anti-jamming ability in complex electromagnetic environment is becoming higher and higher. Suppression jamming is to cover or submerge useful signals with noise or similar jamming signals to prevent radar from detecting target signals. In order to evaluate the influence of suppression jamming on airborne warning radar, the influence of suppression jamming on the detection probability and detection distance of warning radar is analyzed. The variation of radar detection range and detection probability in complex electromagnetic environment compared with normal detection is given by flight test. It also provides a reference for evaluating the anti-jamming ability of airborne warning radar after being suppressed.

The battlefield environment that modern electronic information equipment faces during use is very complicated, which has become one of the main characteristics of the informationized battlefield. This article starts with the composition and characteristics of a complex electromagnetic environment, references relevant standards, introduces the definition and composition of a complex electromagnetic environment, and summarizes its characteristics. On this basis, this article introduces the general methods of complex electromagnetic environment tests, including digital simulation tests, semi-physical simulation tests, and full-physical simulation tests. Among them, in the full physical simulation test, an equivalent method is generally used to achieve it. At the same time, this article introduces test evaluation methods, including element-level evaluation and effectiveness-level evaluation. Combining engineering practice, this paper puts forward the difficulties of constructing a complex electromagnetic environment. It is an inevitable requirement for the development of weapons and equipment to carry out comprehensive experimental research on the complex electromagnetic environment of aircraft, and to be able to assess the combat capability of the product. It is also an objective requirement for the development trend of the information military.

Introduction. The Russian telecommunications industry is on the threshold of introducing 5G/IMT-2020 (5G) mobile communications. The expected technological innovations of the new generation standard will lead to an increase in the capacity of mobile operators ‘ networks, data transfer speeds, the emergence of new scenarios for the use of mobile communications and the development of innovative digital services. This will contribute to economic growth by increasing labour productivity, automation and introducing new technologies in various economy and human activity areas. At the same time, the electromagnetic environment (EMO) in the areas where people stay will also change. The purpose of the study is to consider the unique features of the architecture of the 5G network to predict the impact on the population of electromagnetic fields (EMF) of the radio frequency (RF) range. Material and methods. The study is analytical. The information base of the research was Russian strategic documents on the development of 5G technologies, articles published in domestic and foreign journals. Results. The primary input data for the construction of 5G networks are presented, allowing us to evaluate EMO and identify the new technology features that are significant in terms of the impact of RF electromagnetic fields on the population. The 5G network uses previously unused RF bands and new types of antennas. With the introduction of 5G, the density of base stations (BS) and access points will significantly increase, the heights of BS antennas will decrease, and the spatial and temporal characteristics of electromagnetic radiation will change substantially. Conclusion. The architecture of the 5G network differs significantly from the mobile communication standards of previous generations. The introduction of 5G networks will lead to a significant change in the electromagnetic background in the environment. An urgent task is to develop a theory of hygienic regulation of RF EMF for the population in a complex electromagnetic environment with simultaneous operation of 5G networks and previous generations and new approaches to determining the levels of EMF in the environment by computational and instrumental methods.

For research the radar network operation capability which are effected by complex electromagnetic environment, the paper modeling the radar operation capability cloud rules arithmetic in complex electromagnetic environment and radar network operation capability evaluation model. The operation capability of radar network, which are constituted by 3 radars in complex electromagnetic environment, is simulated & evaluated by Netlogo 3D. The result show that the operation capability of radar is impacted remarkably by complex electromagnetic environment, it could improve the operation capability availably by take the network mode.

Third order time and frequency analysis has exhibited great potential for correlation analysis of multi-sensor datasets, but is usually presented as separate time domain and frequency domain approaches. A combined framework of both frequency domain and time domain has rarely been used. This paper proposes a non-parametric third order time and frequency domain framework which used two dimensional Fourier transforms to bridge the gap between time domain and frequency domain. A unified framework offers flexibility and efficiency to apply to data. In this paper we study neural spike train data treated as stochastic point processes. In time domain direct analysis, third order cumulant densities of spike trains are applied, which need all first-, secondand third order product densities to be calculated before constructing the third order cumulant density, which brings additional challenges. The novelty in this study is that a new framework is proposed which can offer an alternative approach without calculating lower order quantities and can reveal nonlinear relationship between neural recordings. The results show that the present framework provides a novel non-parametric method to estimate both time and frequency domain measurements which is applicable to neural spike trains.

Electronic jamming is the key technology of electronic countermeasure, for which models and simulations are studied on noise jamming, deception jamming, and chaff jamming. In the noise jamming, the simulation analysis of radio frequency noise jamming is conducted and the theoretical models of other forms of noise jamming are built. The simulation analysis of range-gate pull off (RGPO) is carried out in the deception jamming. In addition, theoretical modeling and simulation analysis of chaff jamming are carried out with the Monte Carlo method. Simulation results show that the models are correct and can be used to simulate the statistical characteristics of chaff jamming. With the development and wide application of electronic technology, radar, communication, navigation, and IFF signals constitute a complex electromagnetic environment. It is a must to study electronic jamming technology in the complex electromagnetic environment, which will play an indispensable role in the construction of information team and victory in the countermeasure of information technology.

Conventional time-frequency Transformers primarily focus on the global features of signals in the time-frequency domain while neglecting the local features in both the time domain and frequency domain. This limitation hinders the ability of the model to effectively capture the shared features among time, frequency, and time-frequency representations. To address this issue, a Multi-Branch Joint Time-Frequency Transformer (MBJTF-Transformer) is proposed for domain generalization (DG) fault diagnosis of rotating machinery. Specifically, a time-branch Transformer is designed to extract temporal features, while a frequency-branch Transformer captures frequency-domain information. In addition, a time-frequency Transformer is employed to learn the shared representations across time, frequency, and time-frequency domains. Finally, a multi-decision fusion strategy of MBJTF-Transformer is adopted to enhance the generalization capability of the model. Experimental results on both the SCARA (Selective Compliance Assembly Robot Arm, SCARA) dataset and the PU (Paderborn University) bearing dataset demonstrate that the proposed MBJTF-Transformer achieves superior DG performance compared to multiple state-of-the-art sequential models.

The basins of the inland waterways of the Russian Federation are characterized by a variety of specific navigation features, the destructive effects of which significantly affect the parameters of the purpose of radio navigation systems. Therefore, the task arises to develop a model and estimate the electromagnetic deformation of the high-precision radio navigation field in the basins of the inland waterways of Russia caused by their navigational features. The study and identification of the general navigational features of the basins of the inland waterways of Russia and the assessment of the degree of influence of their destabilizing factors on the quality indicators of the high-precision radio navigation field. New navigation features have been identified in the basins of the inland waterways of Russia, the destructive factors of which deform the high-precision radio navigation field and reduce the quality of transmission of differential corrections. The results obtained confirm a decrease in the accuracy of positioning unmanned vessels in sections of the waterway with a complex terrain topology and electromagnetic environment. At the same time, the positioning accuracy in river basins may deteriorate in local areas from 1.6 times (from 6.8 m to 28.7 m) to 4.3 times (from 27.3 m to 117 m), depending on the electro-magnetic situation and the value of the geometry coefficient. A decrease in the quality of differential correction transmission will be manifested at the boundaries of service areas and range from 1 dB in sparsely populated areas and up to 30 dB in industrial zones. These factors will reduce the safety of navigation, so they must be taken into account when operating ships and designing functional additions to the global nav. The results obtained in the work can be used in the formation and optimization of the topology of control and correction stations of differential additions to the global navigation satellite system and to meet the requirements for the accuracy of positioning of mobile objects in difficult physical and geographical conditions of the terrain and electromagnetic environment.