Vehicular Ad hoc Networks (VANET) is an emerging technology which attracted a lot of attention in recent years. VANETs are used for improving road safety and to provide variety of value added services. There are some security issues and attacks associated with the VANET due to its dynamic changing topology. This paper focuses on the detection of jamming attack and providing solution to this att...

We study the origin of the scaling behavior in frictionless granular media above the jamming transition by analyzing their linear response. The response to local forcing is non-self-averaging and fluctuates over a length scale that diverges at the jamming transition. The response to global forcing becomes increasingly nonaffine near the jamming transition. This is due to the proximity of floppy...

Physical-layer and MAC-layer defense mechanisms against jamming attacks are often inherently reactive to experienced delay and loss of throughput after being attacked. In this paper, we study a proactive defense mechanism against jamming in multi-hop relay networks, in which one or more network sources introduce a deceptive network flow along a disjoint routing path. The deceptive mechanism lev...

We determine the form of the complex shear modulus G* in soft sphere packings near jamming. Viscoelastic response at finite frequency is closely tied to a packing's intrinsic relaxational modes, which are distinct from the vibrational modes of undamped packings. We demonstrate and explain the appearance of an anomalous excess of slowly relaxing modes near jamming, reflected in a diverging relax...

The intermittent sampling repeater jamming (ISRJ) can only produce fake point scatterers in the down-range, while the timevarying frequency induced by rotational micro-motion dynamics blurs the image in the cross-range. This paper focuses on the combination of the above two methods to counter the inverse synthetic aperture radar (ISAR). Based on the signal models of coherent ISAR signal process...

⎯A semi-blind source extraction algorithm for noisy mixtures based on a linear predictor is proposed. The novel algorithm is firstly validated using the benchmark data and then is applied to extract array radar signal suffering from jamming interference. The results showed that the novel algorithm can effectively extract the target signal in radar echo. Thus, it has practical application prospe...

The viscous slowing down of supercooled liquids that leads to glass formation can be considered as a classical, and is assuredly a thoroughly studied, example of a ”jamming process”. In this review, we stress the distinctive features characterizing the phenomenon. We also discuss the main theoretical approaches, with an emphasis on the concepts (free volume, dynamic freezing and mode-coupling a...

A performance analysis of a slow frequencyhopped, noncoherent binary frequency-shift keying (SFH/NCBFSK) communication system with rate % convolutional coding and soft decision Viterbi decoding in the presence of partial-band noise jamming is performed. The effect of additive white Gaussian noise is also considered. The system’s performance is severely degraded by partial-band noise jamming, By...

We study the localization of vibrational modes of frictionless granular media. We introduce a new method, motivated by earlier work on non-Hermitian quantum problems, which works well both in the localized regime where the localization length ξ is much less than the linear size L and in the regime ξ L when modes are extended throughout our finite system. Our very lowest frequency modes show “qu...

We study the localization of vibrational modes of frictionless granular media. We introduce a new method, motivated by earlier work on non-Hermitian quantum problems, which works well both in the localized regime where the localization length ξ is much less than the linear size L and in the regime ξ & L when modes are extended throughout our finite system. Our very lowest frequency modes show “...