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Recent advances in distributed in-network data storage and access control have led to active research in efficient and robust data management in wireless sensor networks (WSNs). Although numerous schemes have been proposed this far, most of them do not provide enough attention towards exploiting user hierarchy and sensor heterogeneity, which is quite a practical issue especially when deploying WSNs...
The opportunistic large array (OLA) with transmission threshold (OLA-T) is a simple form of cooperative transmission that limits node participation in broadcasts. Performance of OLA-T has been studied for disc-shaped networks. This paper analyzes OLA-T for strip-shaped networks. The results also apply to arbitrarily shaped networks that have previously limited node participation to a strip. The analytical...
In this paper, we construct rate compatible low density parity-check (RC-LDPC) codes from a new perspective. In traditional methods, the columns of parity-check matrix, each of which corresponds to a bit of a codeword, are deleted or added to obtain codes at various rates. Different from them, only the rows of parity-check matrix are operated in our method. Since the number of columns remains unchanged,...
In this paper, we consider the reliable data fusion problem in a tactical environment in the presence of adversary. First, we characterize malicious behavior of compromised sensors assuming probabilistic models. Performance of the fusion process, in the presence of malicious sensors, is then quantified. The performance analysis shows that malicious sensors incur significant degradation on the fusion...
With the phenomenal success and productivity of terrestrial networks, there is interest in using similar technology in space. For instance, there currently are projects aimed at deploying Internet routers in space. In this paper, we discuss the general concept of connecting a cluster of satellites with a local area network. We discuss the advantages and challenges of such a network, as well as possible...
In spite of its proven advantage, realization of affordable multi-functional phased-arrays, combining multiple communication apertures, is hindered by size, weight, and power consumption (SWaP) and cost issues. Incremental improvements in both transmit and receive analog RF chains are being pursued. However, it is difficult to expect revolutionary advances in phased array SWaP using architectures...
A recent feasibility study suggests that a Service Oriented Architecture (SOA) will be central within the NATO Network Enabled Capabilities information infrastructure. An important element of a SOA is the service discovery process, but existing solutions are not sufficient in military networks. We suggest to use a robust Peer-to-Peer (P2P) network as a complement. Unfortunately, available P2P search...
The necessity of taking into account high-level information has recently been reported by the information fusion community. We previously presented an approach for high-level symbolic fusion that relies on the use of the conceptual graphs model. Domain knowledge is a major point of the fusion process. The use of conceptual graphs for knowledge representation eases the process of expressing domain...
Wireless sensor networks (WSNs) can be used by the military for a number of purposes such as monitoring or tracking the enemies and force protection. Unlike commercial WSNs, a tactical military sensor network has different priority requirements for military usage. Especially in the remote large-scale network, topology, self-configuration, network connectivity, maintenance, and energy consumption are...
Future wireless communication systems should be flexible to support different waveforms (WFs) and be cognitive to sense the environment and tune themselves. This has lead to tremendous interest in software defined radios (SDRs). Constraints like throughput, latency and low energy demand high implementation efficiency. The tradeoff of going for a highly efficient WF implementation is the increase of...
In this paper, the expression for symbol error rate (SER) or BER of linear modulation in Rayleigh fading as a function of signal-to-noise ratio (SNR), modulation scheme and diversity order, is inverted, thereby giving SNR as a function of SER. The key is to represent the PDF (or MGF) by a Maclaurin series and discard all but the first one or two terms. For large SNRs, the first term in the series...
FPGAs have become a ubiquitous part of today's processing technology. Their use has grown from traditional glue logic interfaces of the past to the most advanced information processing systems used by core Internet routers and high-performance computing systems. What remains common throughout this evolution is the desire to integrate more functionality in less space while using less power and at a...
The Mobile User Objective System (MUOS) is largely based on 3rd Generation Partnership Project (3GPP) standards, however, these standards are intended for terrestrial mobile communications networks. As a result of incorporating geosynchronous satellites into the design (e.g., extended propagation delays, power, cell size), modifications to the 3GPP procedures, such as moving control of cell selection,...
The U.S. Army has developed a modular architecture for the high bandwidth military tactical satellite communications terminal domain with flexible multiband and multimode capabilities. The architecture was validated and verified using modeling and simulation. The artifacts generated by the model can be used to develop the DoDAF views to obtain certifications for DoD enterprise interoperability, information...
Scintillation mitigation is an important aspect of free-space optical (FSO) communications link design. While a number of hardware-based mitigation techniques have been proposed in the literature and deployed in experimental systems (e.g., aperture averaging, wavelength diversity, etc.), novel baseband signal processing approaches have the potential to complement - or even supplant - these traditional...
Friendly force tracking systems (FFTS) are the lowest echelon of command and control information systems (C2IS) in any army command and control architecture. Their initial goal is to provide near real-time information about own troops position. However, in foreseeable current empty battlefields as well as in asymmetric confrontations at least two extra functionalities are required: 1) sensor integration...
In crypto-partitioned networks classified clear text enclaves (i.e., red enclaves) are interconnected over an enciphered unclassified transit network (i.e., black network) via IPSEC tunnels. Thus, packets are encrypted before they are allowed to cross from red networks to a shared black network. Currently, there is no solution that can provide efficient end-to-end IntServ QoS signaling across crypto-partitioned...
Traditionally, digital signal processing (DSP) is performed using fixed-point or integer arithmetic. The algorithm is carefully mapped into a limited dynamic range, and scaled through each function in the datapath. This requires numerous rounding and saturation steps, and can adversely affect the algorithm performance. Use of floating-point arithmetic provides a large dynamic range and greatly simplifies...
Studying the behavior of mobile ad-hoc networks (MANETs) is essential for predicting the performance of the network over the mission/application duration. In this work, we develop a framework for automating the network design to aid the user in tuning the design parameters as the mission progresses. We show the different states that the automated design manager (ADM) goes through to support different...
The emerging technologies of multiple, cooperative unmanned systems have brought in an exciting period of possibilities, possibilities of solving challenging problems in medical, social, engineering, and military communities. The technologies have also introduced a growing number of new challenges such as resource allocation, communication and coordination, establishment of consensus, and control...
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