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Military force structures are becoming increasingly complex and net-centric as new technologies are developed and deployed. As such, there is an ever increasing need to provide system-of-systems (SoS) analysis tools to assist in evaluating a military combat team's survivability, lethality, sustainment and logistics. Evaluation of networked communications as part of this analysis is often overlooked...
In this paper we discuss issues in testing various cognitive fusion algorithms for situation management. We provide a proof-of-principle discussion and demo showing how gaming technologies and platforms could be used to devise and test various fusion algorithms, including input, processing, and output. We argue that the proof-of-principle warrants further work on more advanced test beds and methods...
In this paper, we investigate a phase randomization technique in order to modify the coherence structure of a chaotically modulated signal. Phase randomization is shown to reduce the detectability of cyclostationary features, introduced by the constant chip rate of the chaotically modulated signal. The chaotic modulation scheme is based on the symbolic dynamics of a modified Bernoulli shift map and...
In this work, we consider a multi-hop cognitive radio network with multiple flows. The challenges induced by the random behaviors of the primary users are investigated in a stochastic network utility maximization framework. To fully utilize the scarce network resource, we propose an optimal traffic splitting scheme for each source node to explore multiple paths effectively. In addition, the algorithm...
The Network Centric Operations Industry Consortium (NCOIC) provides guidance for network centric operations (NCO) interoperable systems. The NCO interoperability framework (NIF) [1] provides an organizational construct and repository for enabling this guidance. NIF is a framework that assists industry to design interoperable systems. NIF is based upon standards, including patterns, principles, and...
Determining an optimal position of an antenna on a platform is not always intuitive. This paper examines the implementation of a genetic algorithm (GA) within XFdtd, a finite difference time domain (FDTD) solver, for its effectiveness in determining an optimal antenna position when compared to a brute force method. XFdtd uses the FDTD method to solve general electromagnetic problems. Built into XFdtd...
Unequal error protection (UEP) and rateless coding are both methods used to combat channel uncertainty. With a rateless code, the code rate automatically adapts to the channel quality through the use of incremental redundancy. However, a rateless code lacks the ability to differentiate priorities and all bits suffer the same long delay in poor channel conditions. In contrast, UEP ensures reliable...
Network science has recently received a considerable amount of attention from the military and research communities. In this paper we analyze two military scenarios from a network science perspective. We discuss the pros and cons of problem solving for these scenarios using the current fragmented approach versus applying a unified view across three domains: social/cognitive, information, and communication...
The Army Technical Reference Model (TRM) is a fundamental component of the Army Enterprise Architecture suite of reference models. This paper describes the TRM, how it facilitates enterprise architecture integration and system interoperability, how it maps to other key DoD architecture models, and its value to the acquisition community. It describes how it supports Program Managers for efficiently...
To support research in wireless mobile ad hoc networks, the U.S. Army Research Laboratory (ARL) and Naval Research Laboratory (NRL) have worked jointly to establish an advanced emulation environment. A key component is a mobile ad-hoc network emulation testbed where algorithms and applications can be subjected to representative wireless network conditions. The testbed is based on a version of the...
In wireless networks, communication links may be subject to random fatal attacks: for example, sensor networks under sudden power losses or cognitive radio networks with unpredictable primary user spectrum occupancy. Under such circumstances, it is critical to quantify how fast and reliably information can be collected over attacked links. In our previous work, we studied such channels by considering...
This paper investigates the invariant detection problem of quadrature phase-shift keying (QPSK) direct sequence spread spectrum (DS-SS) signals in additive white Gaussian noise (AWGN). Using the complex Gaussian mixture signal model and invariance principle, we consider the constant-false-alarm-rate (CFAR) invariant detectors and other sub-optimal invariant tests, including the uniformly-most-powerful-invariant...
Electronic warfare (EW) is commonly divided into three subfields: electronic warfare support (ES), electronic attack (EA), and electronic protection (EP). Among them, ES systems take charge of collecting and analyzing the received signal from enemy's emitters and then provide the processed information to friendly EA and EP systems. The information is of critical importance because it is the first...
Owing to the extensive use of commercial wide-band SATCOM systems by the Department Of Navy (DON) and the Department of Defense (DOD) in general, designers and operators of such systems need to investigate and analyze the performance of a broad range of deployment options with respect to communications requirements under a given warfighting scenario, and show the effects of these alternatives on these...
The wideband global SATCOM (WGS) system is currently operational in the Pacific Ocean using WGS1 (175E). GBS traffic is supported in that theater today using the digital video broadcast by satellite (DVB-S) and operates using terminals originally designed for operation using the UHF follow-on satellite (UFO8). These terminals can now operate over WGS1 and UFO8. GBS is planned to migrate to the joint...
The performance of an oversampled multiband wideband digital receiver is presented in this paper. Unlike previous works that assume a single channel receiver and a conventional analog-to-digital converter (ADC), where the quantization error is modeled as an additive uniform random noise, this paper includes the effects of an oversampled sigma-delta (??-??) ADC with noise shaping and an automatic gain...
In this paper we formulate OFDM signals based on explicit pulse shaping filtering. A rectangular pulse in time domain for shaping filtering is most often used, but it has SNR loss compared to a shaping filter with a brick-wall frequency domain filter since in practice both require guard time or guard band. Our formulation of OFDM signal based purely on shaping filter may provide a common platform,...
The Crame??r-Rao bound for the joint estimator of carrier frequency offset, carrier phase offset, and symbol timing offset for offset QPSK is derived and used to identify ??good?? training sequences. Conveniently, sequences that repeat a single OQPSK constellation point are found to be the ??best?? for all three estimators when half-sine pulse shaping is used.
Most communication styles in tactical networks are one-to-many communications, which is multicast transmission. Recently, tactical networks has been evolving to Ad-Hoc-like distributed networks with OFDM-based Wideband Networking Waveform (WNW). In this paper, novel rate-adaptive multicast transmission method over OFDM-based wireless networks is proposed. Transmission rate for wireless multicast over...
As electronic warfare (EW) environment has rapidly changed to be more complex, ambiguity in detecting and identifying enemies' radars also has increased in electronic warfare support (ES) systems. To overcome this critical problem by the limitation of the conventional detection and identification method based on the inter-pulse modulation characteristic such as pulse repetition interval (PRI) and...
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