45 research outputs found

    Advanced Timing Circuit for Magnetization of AMR Magnetometer

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    This contribution describes the invention of Magnetometer with protection against detection by electronic countermeasure (ECM) registered by Czech patent office as patent no. 305322.[1] Magnetic sensors are often part of dual use or security instruments and equipment. For this purpose, it is very interesting to build a sensor, which is hidden against electronic countermeasure. In this case, the level and behavior of electromagnetic noise produced by a sensor has become very important. Further, there has been a significant growth of the electromagnetic compatibility of electronic devices. As the consequence of this growth, there is a continuous process of making strict standards focused on the electromagnetic radiation of electronic devices. Sensors technology begins to be a part of these issues due to the increasing usage of sensors bandwidth and the approach to frequency of radio communication band. Nowadays, microcontrollers and similar digital circuits are integrated into sensors devices and it brings new sources of electromagnetic radiation in modern smart sensors

    Electronic countermeasures applied to passive radar

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    Passive Radar (PR) is a form of bistatic radar that utilises existing transmitter infrastructure such as FM radio, digital audio and video broadcasts (DAB and DVB-T/T2), cellular base station transmitters, and satellite-borne illuminators like DVB-S instead of a dedicated radar transmitter. Extensive research into PR has been performed over the last two decades across various industries with the technology maturing to a point where it is becoming commercially viable. Nevertheless, despite the abundance of PR literature, there is a scarcity of open literature pertaining to electronic countermeasures (ECM) applied to PR. This research makes the novel contribution of a comprehensive exploration and validation of various ECM techniques and their effectiveness when applied to PR. Extensive research has been conducted to assess the inherent properties of the lluminators of Opportunity to identify their possible weaknesses for the purpose of applying targeted ECM. Similarly, potential jamming signals have also been researched to evaluate their effectiveness as bespoke ECM signals. Whilst different types of PR exist, this thesis focuses specifically on ECM applied to FM radio and DVB-T2 based PR. The results show noise jamming to be effective against FM radio based PR where jamming can be achieved with relatively low jamming power. A waveform study is performed to determine the optimal jamming waveform for an FM radio based PR. The importance of an effective direct signal interference (DSI) canceller is also shown as a means of suppressing the jamming signal. A basic overview of counter-ECM (ECCM) is discussed to counter potential jamming of FM based PR. The two main processing techniques for DVB-T2 based PR, mismatched and inverse filtering, have been investigated and their performance in the presence of jamming evaluated. The deterministic components of the DVB-T2 waveform are shown to be an effective form of attack for both mismatched filtering and inverse filtering techniques. Basic ECCM is also presented to counter potential pilot attacks on DVB-T2 based PR. Using measured data from a PR demonstrator, the application and effectiveness of each jamming technique is clearly demonstrated, evaluated and quantified

    Optimised soft-core processor architecture for noise jamming

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    M.Ing. (Electrical & Electronic Engineering)Abstract: Noise jamming is a traditional electronic counter measure (ECM) that existed since the establishment of electronic warfare (EW). Traditional noise jamming techniques have been shown to be failing when interacting with intelligent Radar systems such as pulse Doppler radar. Hence there is a need to introduce new noise jamming techniques with digital architecture that will provide improved performance against smart pulse Doppler radar. The work is undertaken to investigate the feasibility of digitizing noise jamming. It focuses on analog-to-digital conversion optimization towards noise jamming architecture, as a result digitization will allow for an opportunity for adaptation of intelligent processing that previously didn’t exist. In this dissertation, certain contributions to the field of noise jamming were made by introducing state of the art odd/even order sampling architecture by proving four case studies. Case study 1 experimentally investigates sample frequency behaviour. Case study 2 uses simulation to investigate step-size and dynamic range behaviour. Case study 3 uses FPGA implementation and SNR to investigate quantization error behaviour. Case study 3 also uses SNR to investigate superiority of proposed odd/even order sampling. Lastly case study 4 uses field measurements, FPGA implementation and SNR to investigate practical implementation of digitized noise jamming. The main contribution is concerned with an architecture that digitizes, reduces sample frequency, optimizes digital resource utilization while reducing noise jamming signal-to-noise ratio. The approach evaluates and empirically compares three sampling techniques from lecture Mod-Δ, Mod-Δ (Gaussian) and Mod-Δ (Sinusoidal) with proposed novel odd/even order sampling. Sampling techniques are evaluated in terms of quantization error, mean square error and signal-to-noise ratio. It was found that the proposed novel odd/even order sampling achieved most case SNR performance of 6 dB in comparison to 18 dB for Mod-Δ. Sampling frequency findings indicated that the proposed novel odd/even order sampling had achieved sampling frequency of 2 kHz in comparison to 8 kHz from traditional 1st order sigma-delta. Dynamic range findings indicated that the proposed odd/even order sampling achieved a dynamic range of 1.088 volts/ms in comparison to 1.185 volts/ms from traditional 1st order sigma-delta. Findings have indicated that the proposed odd/even order sampling has superior SNR and sampling frequency..

    Radar Signal Processing for Interference Mitigation

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    It is necessary for radars to suppress interferences to near the noise level to achieve the best performance in target detection and measurements. In this dissertation work, innovative signal processing approaches are proposed to effectively mitigate two of the most common types of interferences: jammers and clutter. Two types of radar systems are considered for developing new signal processing algorithms: phased-array radar and multiple-input multiple-output (MIMO) radar. For phased-array radar, an innovative target-clutter feature-based recognition approach termed as Beam-Doppler Image Feature Recognition (BDIFR) is proposed to detect moving targets in inhomogeneous clutter. Moreover, a new ground moving target detection algorithm is proposed for airborne radar. The essence of this algorithm is to compensate for the ground clutter Doppler shift caused by the moving platform and then to cancel the Doppler-compensated clutter using MTI filters that are commonly used in ground-based radar systems. Without the need of clutter estimation, the new algorithms outperform the conventional Space-Time Adaptive Processing (STAP) algorithm in ground moving target detection in inhomogeneous clutter. For MIMO radar, a time-efficient reduced-dimensional clutter suppression algorithm termed as Reduced-dimension Space-time Adaptive Processing (RSTAP) is proposed to minimize the number of the training samples required for clutter estimation. To deal with highly heterogeneous clutter more effectively, we also proposed a robust deterministic STAP algorithm operating on snapshot-to-snapshot basis. For cancelling jammers in the radar mainlobe direction, an innovative jamming elimination approach is proposed based on coherent MIMO radar adaptive beamforming. When combined with mutual information (MI) based cognitive radar transmit waveform design, this new approach can be used to enable spectrum sharing effectively between radar and wireless communication systems. The proposed interference mitigation approaches are validated by carrying out simulations for typical radar operation scenarios. The advantages of the proposed interference mitigation methods over the existing signal processing techniques are demonstrated both analytically and empirically

    DRONE DELIVERY OF CBNRECy – DEW WEAPONS Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD)

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    Drone Delivery of CBNRECy – DEW Weapons: Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD) is our sixth textbook in a series covering the world of UASs and UUVs. Our textbook takes on a whole new purview for UAS / CUAS/ UUV (drones) – how they can be used to deploy Weapons of Mass Destruction and Deception against CBRNE and civilian targets of opportunity. We are concerned with the future use of these inexpensive devices and their availability to maleficent actors. Our work suggests that UASs in air and underwater UUVs will be the future of military and civilian terrorist operations. UAS / UUVs can deliver a huge punch for a low investment and minimize human casualties.https://newprairiepress.org/ebooks/1046/thumbnail.jp

    Electronic warfare self-protection of battlefield helicopters : a holistic view

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    The dissertation seeks to increase understanding of electronic warfare (EW) self-protection (EWSP) of battlefield helicopters by taking a holistic (systems) view on EWSP. It also evaluates the methodologies used in the research and their suitability as descriptive tools in communication between various EWSP stakeholders. The interpretation of the term "holistic view" is a central theme to the dissertation. The research methodology is bottom-up – which is necessary since no previous work exists that could guide the study – and progresses from analysis to synthesis. Initially several methods are evaluated for presenting findings on EWSP, including high-level system simulation such as Forrester system dynamics (FSD). The analysis is conducted by a comprehensive literature review on EW and other areas that are believed to be of importance to the holistic view. Combat scenarios, intelligence, EW support, validation, training, and delays have major influence on the effectiveness of the EWSP suite; while the initial procurement decision on the EWSP suite sets limits to what can be achieved later. The need for a vast support structure for EWSP means that countries with limited intelligence and other resources become dependent on allies for support; that is, the question of EWSP effectiveness becomes political. The synthesis shows that a holistic view on EWSP of battlefield helicopters cannot be bounded in the temporal or hierarchical (organizational) senses. FSD is found to be helpful as a quality assurance tool, but refinements are needed if FSD is to be useful as a general discussion tool. The area of survivability is found to be the best match for the holistic view – for an EWSP suprasystem. A global survivability paradigm is defined as the ultimate holistic view on EWSP. It is suggested that future research should be top-down and aiming at promoting the global survivability paradigm. The survivability paradigm would give EWSP a natural framework in which its merits can be assessed objectively.reviewe

    The probability of detecting and tracking RADAR targets in clutter at low grazing angles

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    Modern military acquisition and tracking RADARs are required to operate against aircraft and missiles specifically designed to have minimal radar cross section (RCS) and which fly at very low level to take maximum advantage of terrain screening. A model for predicting system performance is necessary for a range of terrain types in varying precipitation and seasonal cultural conditions. While the main degradation is from surface clutter and denial of sightline due to terrain and other local obstructions, several other factors such as multipath propagation, deliberate jamming and even operator performance contribute to the total model. The possibility that some radars may track obscured targets, however briefly, by using the diffraction path, is of particular interest. Although this report critically examines each of the contributory factors in order to select optimum values for inclusion in an overall computer prediction model; a new surface clutter model is specifically developed for sloped terrain using actual clutter measurements. The model is validated by comparison with an extensive survey of worldwide clutter results from both published and unpublished sources. Certain constraints have been necessary to restrict the study to a manageable size, while meeting the requirements of the sponsors. Attention is therefore focussed upon performance prediction for typical mobile tracking radar systems designed for operation against small RCS low level targets flying overland

    Unmanned Aircraft Systems in the Cyber Domain

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    Unmanned Aircraft Systems are an integral part of the US national critical infrastructure. The authors have endeavored to bring a breadth and quality of information to the reader that is unparalleled in the unclassified sphere. This textbook will fully immerse and engage the reader / student in the cyber-security considerations of this rapidly emerging technology that we know as unmanned aircraft systems (UAS). The first edition topics covered National Airspace (NAS) policy issues, information security (INFOSEC), UAS vulnerabilities in key systems (Sense and Avoid / SCADA), navigation and collision avoidance systems, stealth design, intelligence, surveillance and reconnaissance (ISR) platforms; weapons systems security; electronic warfare considerations; data-links, jamming, operational vulnerabilities and still-emerging political scenarios that affect US military / commercial decisions. This second edition discusses state-of-the-art technology issues facing US UAS designers. It focuses on counter unmanned aircraft systems (C-UAS) – especially research designed to mitigate and terminate threats by SWARMS. Topics include high-altitude platforms (HAPS) for wireless communications; C-UAS and large scale threats; acoustic countermeasures against SWARMS and building an Identify Friend or Foe (IFF) acoustic library; updates to the legal / regulatory landscape; UAS proliferation along the Chinese New Silk Road Sea / Land routes; and ethics in this new age of autonomous systems and artificial intelligence (AI).https://newprairiepress.org/ebooks/1027/thumbnail.jp
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