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The increasing prevalence of mobile malware has driven the need for emulated, dynamic analysis techniques. Unfortunately, emulating mobile devices is nontrivial because of the different types of hardware features onboard (e.g., sensors) and the manner in which users interact with their devices as compared to traditional computing platforms. To evaluate this, our research focuses on the enumeration...
Multilateration schemes presented in literature generally focus on deriving a minimum solution. The problem of how to make optimal use of the information about specific spatial configurations of the transmitter of interest and the associated set of observers in a wireless network is not generally considered. Such considerations are especially important when using Time Difference of Arrival methods...
Obtaining precise geolocation estimates for mobile devices requires knowledge of the local propagation velocity of light. Under common atmospheric conditions, incorrect propagation velocity estimates introduce systemic dilution of precision using time difference of arrival techniques. Modeling local propagation velocity as a function of common local meteorological variables yields corrected velocity...
In this paper, we present a novel energy consumption analysis of the flow-specific Cooperative Wireless Sensor Network Medium Access Control (CWS-MAC) protocol utilizing a nine-state radio energy model that includes both steady state and transient state energy consumption behavior. CWS-MAC is a traffic-adaptive, energy-efficient medium access scheme that has been shown in the literature to outperform...
This paper implements spectrum sensing using a radio frequency sensor network and analyzes the performance of this implementation through simulation. A sensor network based cooperative wideband spectrum sensing scheme is proposed for the implementation of this task. In the proposed scheme, wavelet-based multi-resolution spectrum sensing, which was originally proposed for cognitive radio applications,...
Space-based networks have long been proposed to support a myriad of both space-based and terrestrial-based applications. While much research has been done on the individual systems that will comprise this network, it was not until recently that the system was examined as a whole utilizing the tools of systems of systems engineering to provide integration and optimization. In this work, we continue...
The energy efficiency trade-offs available between centralized and distributed solutions in unattended wireless sensor network deployments such as those that support remote battlefield monitoring remain an open research question. In this paper, we compare the relative energy efficiency of these two approaches in multi-hop wireless sensor networks. We develop a framework that includes both total and...
Current wireless sensor network applications face challenging power constraints that demand low duty cycles. In this paper, we propose an energy-efficient, flow-specific medium access scheme that is capable of achieving low duty cycles while taking advantage of the performance improvements available through a flow-specific medium access approach. The scheme is based on an adaptive sleep and wake cycle...
A method for file transfer utilizing forward error correction (FEC) to pass traffic over deployed wireless sensor networks is studied. The entire wireless sensor network is modeled as an error-prone virtual physical link. Previous work in the area of terminal communication across the sensor network is expanded upon to include file transfer in order to provide a more capable channel and a basis for...
In this paper, we formally introduce the novel concept of traffic-adaptive, flow-specific medium access control and show that it outperforms contention, non-contention and hybrid medium access schemes. A traffic-adaptive, flow-specific mechanism is proposed that utilizes flow-specific queue size statistics to select between medium access modes. A general model for traffic-adaptive, flow-specific medium...
Several recent publications have sought to adopt a system-of-systems approach to view the ballistic missile defense system as a large-scale, wireless network. This approach implicitly relies on an effective medium access scheme that can accommodate the large propagation delays encountered in a satellite network. While existing satellite networks typically employ a form of time division multiple access,...
We present the design of a randomly distributed radio frequency signal detection and reception array constructed of wireless sensor network nodes. The design stresses initial signal detection using the wireless network array. All other array operations depend on first detecting a signal of interest prior to activating follow-on sequences of signal processing, potentially including geolocation of the...
Collaborative beamforming can be used in a wireless sensor network to increase the effective communication range of the network. In this paper, the power consumption of existing least squares based beamforming solutions is analyzed and an energy-efficient, distributed algorithm for beamformer weight calculation is proposed. Simulation results are provided to demonstrate that the proposed algorithm...
This paper proposes a source localization scheme using random arrays of wireless sensors that addresses multipath propagation. Taking advantage of the dominant reflections, the proposed solution finds the location of a signal source by triangulation using the direction of arrival estimations of both the line-of-sight and the reflected components. It uses a space division multiple access, spread spectrum-based...
Medium access control for a distributed cooperative wireless sensor network is examined. Using a quality-of-service approach, the sensor node traffic (control and data packets) within these cooperative networks is characterized. A novel medium access control mechanism, cooperative wireless sensor medium access control (CWS-MAC), is proposed to meet the requirements of the control and data traffic...
A beamforming approach can be used in a wireless sensor network (WSN) to increase the effective communication range of the network. In this paper, the impact on array performance of node position deviations with respect to the ideal array element locations is examined and a distributed beamforming algorithm is proposed to compensate for these position deviations. Simulation results are provided to...
In this paper, the unique nature of direction finding in an RF environment against an uncooperative emitter is presented. Specifically, the focus is on power management in a wireless antenna array. This paper will present two competing methods of power management. Both methods will use a Least Mean Squares (LMS) adaptive beamforming algorithm to compensate for grating lobes that are present in the...
We present an energy-aware approach for enabling communication between a wireless ground-based sensor network, and an overhead unmanned aerial vehicle (UAV). Specifically, we present a technique for assembling a subset of sensor nodes into a distributed antenna array useful for beamforming. A small subset of sensor nodes receives and aggregates information gathered by the network, and forms a distributed...
In this paper, the unique nature of power management in a wireless distributed antenna system is presented. The primary objective is to create a power efficient methodology to steer the beam to the target in order to enhance collection. This paper will present two competing methods of power management. Both methods use a least mean squares (LMS) adaptive beamforming algorithm to allow for beam steering...
We analyze the optimal number of sensor nodes that should participate in a beamforming process in order to minimize the energy expended by nodes in a sensor network. As we increase the number of sensor nodes involved in beamforming (for a fixed energy per bit to noise power spectral density required at the receiver), the transmit power of each node is significantly reduced, but the overhead in implementing...
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