Intentional Interference Research Articles

Topoanalysis as Narrative Technique in John Cheever’s Architecture of Short Fiction

The backlash of recent biographies of the American “Chekhov of Suburbs” as an ill-tempered alcoholic bisexual with sharp edges of paranoia might serve to justify Cheever’s clumsy, fragmented narratives of grumpy middle class American male commuters who are about to drown in their matrimonial abyss. The present paper’s approach is, however, to avoid psychobiography in favor of stylistic defense. Not quite as psychologically neurotic a writer as what the mainstream biographers have claimed, Cheever mastered the architectural design of fiction. An examination of a number of these short stories (excluding his longer novels in which fragmentation is an undeniable weakness) lays bare a kind of spatial consciousness: the Bachelardian notion of topoanalysis as the dominant technique. Whereas the public and private boundaries are naturally trespassed in many stories, such as Another Story and The Enormous Radio, in some others the protagonists embark on an intentional interference in space – from erasing a whole town in Geometry of Love to living another man’s life in Seaside Houses. Topoanalysis seems to be Cheever’s favorite narrative technique to reach phenomenological borders of life, oftentimes in unhomely circumstances where one’s totality is menaced by internal and external forces.

Null Positioning of Dipole Antenna Array Considering Coupling Effect

Antenna array is a set of antennas that are arranged together with different excitations (amplitude and phase) and used in beamforming techniques. The difference in phases are combined together to make the array acting like a single antenna with better steering capability over a single antenna. However, the receiving antenna arrays are influenced by intentional or unintentional interference. In this research, a null positioning technique has been introduced to the antenna array to efficiently mitigate the interference. An efficient method utilizing Genetic Algorithm (GA) is used to position the nulls in the direction of interference of circular array dipole antennas. In forming the null, GA randomly searches the best fitness function to position the null to any direction. Then, the effect of mutual coupling between the antenna elements is also considered in this research. As a result, the accuracy of radiation pattern of antenna array will be increased. It is observed that the mutual coupling decreases when the spacing between element increases. The simulation results show that nulls can be steered successfully using GA with and without mutual coupling effect. The mutual coupling effect has been taken into account and need to be considered especially in a closely spaced antenna arrays.

A Comparison of MVDR and LCMV Beamformers’ Floating Point Implementations on FPGAs

Adaptive beamformers are designed with the aim of detection of noise and intentional destructive interference and then removing them from the desired signal. This is done by placing high attenuation in the direction of the destructive signal in the radiation pattern of antenna arrays without attenuating the signal from a known direction. Minimum variance distortionless response and linearly constrained minimum variance are among such algorithms in mobile communications. A short explanation of the theory and weights formulae of these beamformers will be given. Two designs for weights calculations in Simulink with the added library of DSP-Builder tool from Altera will be presented. Quadrature Rectangular decomposition with Modified Gram-Schmidt algorithm is used instead of the direct matrix inversion. All calculations are done in single floating point mode for the required high accuracy. Modelsim has been used for hardware simulation and measuring the required clock cycles. The target FPGA is Aria10 from Altera which has floating point DSP blocks for high-performance computations. Hardware resources usage, power consumption, maximum clock frequency and update rate for different matrix sizes of these two beamformers are compared and discussed. The results are also compared with some other relevant reported works.

Impact evaluation of conducted UWB transients on loads in power-line networks

Abstract. Nowadays, faced with the ever-increasing dependence on diverse electronic devices and systems, the proliferation of potential electromagnetic interference (EMI) becomes a critical threat for reliable operation. A typical issue is the electronics working reliably in power-line networks when exposed to electromagnetic environment. In this paper, we consider a conducted ultra-wideband (UWB) disturbance, as an example of intentional electromagnetic interference (IEMI) source, and perform the impact evaluation at the loads in a network. With the aid of fast Fourier transform (FFT), the UWB transient is characterized in the frequency domain. Based on a modified Baum–Liu–Tesche (BLT) method, the EMI received at the loads, with complex impedance, is computed. Through inverse FFT (IFFT), we obtain time-domain responses of the loads. To evaluate the impact on loads, we employ five common, but important quantifiers, i.e., time-domain peak, total signal energy, peak signal power, peak time rate of change and peak time integral of the pulse. Moreover, to perform a comprehensive analysis, we also investigate the effects of the attributes (capacitive, resistive, or inductive) of other loads connected to the network, the rise time and pulse width of the UWB transient, and the lengths of power lines. It is seen that, for the loads distributed in a network, the impact evaluation of IEMI should be based on the characteristics of the IEMI source, and the network features, such as load impedances, layout, and characteristics of cables.

Effects of Aperture Size on <i>Q</i> factor and Shielding Effectiveness of a Cubic Resonator

Abstract. The EMC properties of a cubic metallic shield are highly affected by its resonances. At the resonant frequencies, the shielding effectiveness (SE) collapses, which results in high field strengths inside the cavity. This can cause failure or even breakdown of electronic devices inside the shield. The resonant behaviour is mainly determined by the quality or Q factor of the shield. In this paper, the effects of the aperture size on the Q factor and the SE of an electrically large, cubic shield are analysed. At first, a method is developed in order to determine the Q factor based on the resonance behaviour of the shield in time domain. Only the first resonance of the shield is considered therefore. The results are evaluated for different aperture diameters and compared with theory for the Q factor. The dominant coupling mechanism of electromagnetic energy into the shield is thus identified. Then the effect of aperture size on the SE is analysed. The excitation of resonances is very probable if the interfering signal is an ultrawideband (UWB) pulse, which constitutes a typical intentional electromagnetic interference (IEMI) scenario. Therefore, the relation between aperture size and SE is analysed using the theory of the transient SE for a broadband signal with a constant spectral density distribution. The results show, that a worst case aperture size exists, where the SE has its minimum.

Multi-Terminal Two-Hop Untrusted-Relay Networks With Hierarchical Security Guarantees

We consider a two-source two-destination two-hop relay network, where all data communication must be kept secret from the relay node. The model considered is the simplest primitive that embodies a multi-transmitter multi-receiver network that needs to communicate sharing an untrusted relay node. We focus on two scenarios. In the first scenario, each source aims to send two messages to be kept secret from the relay: a common message that should be decoded by both destinations, and a private message that should be decoded by the first destination while kept secret from the second one. We define an achievable rate region by utilizing stochastic encoding at the sources, the Gaussian noise cooperative jamming from the destinations, and compress-and-forward at the relay. In the second scenario, each source aims to send a confidential message to its intended destination, which should be kept secret from the other one as well as the relay. We define an achievable rate region using a combination of nested lattice codes and random binning at the sources, structured cooperative jamming from destinations, and scaled compute-and-forward at the relay. We also derive genie-aided outer bounds on the secrecy rate regions. We present numerical results that demonstrate the performance of the proposed achievable schemes. Overall, this paper provides insights into how to utilize an untrusted relay to communicate to destinations with different levels of security clearance, and how intentional interference is an enabler of communication.

Fuzzy-Based Risk Analysis for IT-Systems and Their Infrastructure

This paper introduces a procedural method based on the fuzzy logic and set theory, which analyzes the risk of an IT-System in a facility and its surrounding area. The method analyzes the susceptibility of an electronic system with respect to intentional electromagnetic interferences and classifies the intentional electromagnetic environment (IEME). It extends the well-known statistical-based models fault tree analysis, electromagnetic topology and Bayesian networks (BN) with imprecise data, uncertainness with linguistic terms, and opinions of experts. In a final step, the critical scenarios and the elements and the location that contribute most to the risk are identified, which can be used to enhance the protection level.

Carrier Frequency Recovery for Nyquist and Faster-than-Nyquist Signaling System

Proposed is a new estimator for the carrier frequency recovery in Nyquist and faster-than-Nyquist (FTN) signaling system. Considering the intentional inter-symbol interference caused by FTN, a discrete-time model for synchronization of FTN is built for the first time, which is different from the traditional model based on the Nyquist criterion. The discrete-time model is simplified assumed that the frequency offset is much smaller than the sampling rate and the shaping pulse is time-truncated adopted from the 3GPP standard. Furthermore, a novel frequency estimator with three discrete Fourier transform samples interpolation is proposed for FTN signaling over the additive white Gaussian noise channel. Comparing with the Cramer–Rao bound, numerical results show the performance of new frequency estimator in the transmission system with the Nyquist rate and beyond the Nyquist rate.

Exploiting the Fast Spectral Roll-Off of CPM Sidelobes to Improve Bandwidth Efficiency in Satellite Communications

Simple and efficient carrier-overlapping and interference-reduction techniques are addressed for frequency-division multiplexing–continuous phase modulation (FDM–CPM) schemes. CPM carriers are densely multiplexed (packed) in the frequency-domain, without leaving any guard bands, thus allowing frequency content in adjacent bands to overlap, so as to enhance the bandwidth efficiency. The intentional adjacent channel interference, introduced by carrier-overlapping during transmission, is combated at the receiver front-end using simple interference-reduction filters that are designed to exploit the fast roll-off of CPM spectral sidelobes. The receiver back-end is governed by a serially concatenated CPM iterative demodulation/decoding detector. Numerically optimal carrier-packing ratios are determined with respect to information-theoretic bounds. The presented method does not require cooperation among users, and is extended to QAM and PSK schemes as well. Bit error rate analyses show that the proposed non-cooperative receiver design facilitates bandwidth and energy-efficient communication for both the nonlinear and linear satellite channels, without resorting to multiuser detectors, and becomes an attractive solution when cooperation may not be feasible among users that are geographically spread-out.

Mitigation Techniques to Reduce the Vulnerability of Railway Signaling to Radiated Intentional EMI Emitted From a Train

This paper evaluates several techniques capable of mitigating the impact of low-power radio frequency jammers that interfere with ground-to-train communications. These radio communications are used for railway signaling, and interfering with these signals can have a negative impact on the train operation. Although the commercialization, detention, and use of radiofrequency jammers is strictly forbidden in most countries, they can be easily found on the internet at low cost and unexpectedly switched on by a passenger in a moving train. In this paper, we evaluate and compare the ground-to-train radio communication and intentional electromagnetic interference (IEMI) received signal powers delivered by roof train antennas to the train control command receiver. This comparison is used to deduce the potential zones of interference along the train trajectory and its consequences. Operating at the physical layer, we then propose and evaluate three mitigations techniques that can be used separately or combined to reduce the impact of this type of interference. We show that they can significantly reduce the jamming capability and help us in maintaining railway full operation.

Порівняльний аналіз зразків авіоніки і їх компонентів стосовно до створення методології синтезу інтегрованої авіоніки БПЛА

Мета: Метою цієї роботи є аналіз зразків авіоніки та їхніх компонентів з огляду на створення методології синтезу інтегрованої авіоніки дистанційно-пілотованих та безпілотних аерокосмічних динамічних об’єктів (АДО), яка забезпечує комплексне розв’язання завдань навігації та синергетичного управління АДО в аеронавігаційному просторі. Методи дослідження: Аналіз та постановка завдань є основою для розробки сучасних методів комплексування та обробки первинної інформації, методів розв’язання навігаційних задач, методів розв’язання задач керування в комплексах інтегрованої авіоніки АДО. Зокрема це неінваріантний компенсаційний метод комплексування первинних джерел інформації, комплексні методи кореляційно-екстремальної навігації, метод синергетичного управління АДО. Результати: Використання цих методів дозволить підвищити ефективність вирішення задач навігації і управління як цивільних так і військових АДО, в умовах дії випадкових і навмисних завад, при відмовах елементів авіоніки. Обговорення: Виходячи з наведеного аналізу, можна встановити вимоги до прототипів інтегрованої авіоніки, що розробляється для навігації і управління AДO.

Secure Transmission of Wireless Relaying Systems With Jammer and Multiple-User Selection

In this paper, we investigate the secure transmission of wireless relaying systems with multi-destinations and an eavesdropper (Eve) in Nakagami- $m$ fading channels. To protect the confidential message from leaking to the Eve, an intentional interference is sent from a selected destination. We propose two jammer selection schemes under two typical communication scenarios: 1) the channel state information (CSI) of the Eve is unknown, where a jammer is selected based on the CSI between the selected legitimate receiver and the other destination users and 2) the CSI of the Eve is available, where a jammer is selected based on the CSI between the Eve and the other destination users. To assess the performance of the two proposed schemes, we first derive the exact closed-form expressions of intercept probability and outage probability to evaluate the security and the reliability of the system, respectively. In addition, to evaluate the security and reliability as a whole, we propose a new definition of the security–reliability tradeoff, which allows us to easily optimize the power allocation and improve the performance. Finally, simulation results are provided to verify the availability of the proposed schemes.

A systematic approach for electromagnetic interference risk management

The safety and reliability of electrical and electronic systems are questioned by exposure to electromagnetic environments, as they can suffer from errors, malfunctions and even permanent damage due to caused electromagnetic interference. In particular, cases in which the electromagnetic environment is originated with the intention to cause malfunctions or destructions in key electronic systems, like critical infrastructures, are in the focus of increasing public concern. The technological development of last decades resulted in a situation in which it became necessary to protect critical systems and infrastructure against intentional electromagnetic interference threats. In fact not all critical infrastructures might be vulnerable to such environments, but without a systematic risk assessment the current situation is unknown. The required level of confidence in the protection of electrical and electronic systems against electromagnetic interference can only be achieved by applying a systematic risk management process in all phases of the system lifecycle. This article provides an introduction to the electromagnetic interference risk management process as well as to the Threat Scenario, Effect and Criticality Analysis, a novel electromagnetic interference risk analysis methodology. In the second part of the article particular aspects of the electromagnetic interference risk analysis concerning the data structure of the electromagnetic interference threat scenario and resources available to a potential offender are discussed in detail.

A Comparative Analysis of Adaptive Notch Filtering and Wavelet Mitigation against Jammers Interference

Global Navigation Satellite System (GNSS) receivers are vulnerable to the threats of unintentional interference generated by other communication systems and intentional interference known also as jamming. In particular, the intentional transmission of Radio Frequency (RF) interference with the goal of disrupting one or more of the received GNSS frequency bands can disrupt the operation of GNSS receivers over a wide target area. This paper provides a comparison between two interference mitigation techniques at the digital signal processing level. The traditional adaptive notch filtering has been compared with a more innovative technique based on the use of the Wavelet Packet Decomposition (WPD). Using simulated GNSS jammed scenarios and a software-defined GNSS receiver, results indicate the benefits of WPD relative to notch filtering. Further tests using love interference signals, and both a software and commercial hardware receiver, demonstrate the benefits of WPD in terms of signal quality and position domain metrics.

Issue of reliability–exploitation evaluation of electronic transport systems used in the railway environment with consideration of electromagnetic interference

This study presents notions related to the reliability–exploitation analysis of electronic transport systems, which are used in the railway environment. Intentional or unintentional (stationary or mobile) electromagnetic interference existing in a vast railway area may be the cause of disturbance in its operation. Thus, it is important to ensure correct operation of electronic transport systems in an electromagnetic environment existing in a railway area. The reliability–exploitation analysis of electronic transport systems was conducted with the consideration of electromagnetic interference. This enabled the specification of the values of probability of the system staying in specific states.

Interference Rejection in FH/BFSK System Using Blind Source Separation

This paper introduces a new approach based on blind source separation (BSS) to mit igate intentional interference in BFSK d igital co mmun ication systems using frequency hopping spread spectrum technique. The use of BSS is possible thanks to adopting an adequate selection block to distinguish between the useful signal and other undesirable signals, hence, circu mvent the problem of amb iguity of permutation. An analytical calculation of the probability of error to predict the performance is done. The simulat ion results showed the effectiveness of this approach, whatever the level of the JSR and without using the fast frequency hopping alternative or error-correcting codes.

Risk analysis with a fuzzy-logic approach of a complex installation

Abstract. This paper introduces a procedural method based on fuzzy logic to analyze systematic the risk of an electronic system in an intentional electromagnetic environment (IEME). The method analyzes the susceptibility of a complex electronic installation with respect to intentional electromagnetic interference (IEMI). It combines the advantages of well-known techniques as fault tree analysis (FTA), electromagnetic topology (EMT) and Bayesian networks (BN) and extends the techniques with an approach to handle uncertainty. This approach uses fuzzy sets, membership functions and fuzzy logic to handle the uncertainty with probability functions and linguistic terms. The linguistic terms add to the risk analysis the knowledge from experts of the investigated system or environment.

Joint GNSS Interference Mitigation Approach for Jamming and Spoofing Based on Multi-antenna Array

Jamming and spoofing are the most common and serious threat intentional interferences for Global Navigation Satellite?System (GNSS). A joint GNSS interference mitigation approach is proposed for jamming and spoofing issue based on multi-antenna array in this paper.?Firstly, jamming is suppressed by the subspace technology. Then, spoofing is detected and mitigated by using the weighting vectors obtained by the despread- respread method.?Finally, for maximizing the output of each authentic signal, the despread-respread method is reutilized to form multiple beams pointing at each of the authentic satellites.? Simulation results show that the proposed algorithm can null jamming and spoofing simultaneously. The interference suppression performance of this method is not sensitive to the array manifold?errors and not limited by the prior knowledge of satellites directions.

Fundamental Study on a Mechanism of Faulty Outputs from Cryptographic Modules Due to IEMI

SUMMARYThis paper investigates the mechanism underlying faulty outputs from cryptographic modules due to intentional electromagnetic interference (IEMI), which causes information leakage in electronic devices without disrupting their functions or damaging their components. We show this fault mechanism through experiments using the faulty ciphertexts and pulse injection to a specific round in the encryption process. The experimental results indicate that faulty outputs from cryptographic modules are caused by setup time violation in the cryptographic module.

Experimental Characterization of the Response of an Electrical and Communication Raceway to IEMI

This paper reports the results of two experimental campaigns aimed at studying the high-frequency response of a raceway containing low voltage power, telephone, and Ethernet cables, to external electromagnetic field illumination. The raceway was tested against HPEM transients inside a gigahertz transverse electromagnetic (GTEM) cell and low-power fields inside a reverberation chamber (RC). The high-power electromagnetic (HPEM) tests revealed that the low-voltage power cables have the greatest coupling under a hyperband illumination, compared to telephone and Ethernet cables. The RC tests allowed the determination of statistical transfer functions from random incident field configurations into DM voltage in cable loads. The responses were found to be governed by the raceway under test at the lower frequencies (below 1 GHz). Between 0.2 and 1 GHz, the raceway gives about 10 dB higher coupling than a short patch cable. The difference is even greater at lower frequencies and for shielded cables. In the frequency band 1–3 GHz, little difference was observed between short patch cables and the full raceway, but both were still significantly higher than direct coupling to the measurement card. Beyond 3 GHz, the coupling is clearly dominated by the terminal equipment. The experiments performed in this paper provide a better understanding of the expected induced voltages and currents in commercial cable systems when exposed to intentional electromagnetic interference (IEMI)-like signals.