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Copyright and Reprint Permission: Abstracting is permitted with credit to the source. Libraries are permitted to photocopy beyond the limit of U.S. copyright law for private use of patrons those articles in this volume that carry a code at the bottom of the first page, provided the per-copy fee indicated in the code is paid through Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923...
The overarching theme of this year's conference is Trusted Communications ... Awareness to Action. Topics to be addressed will include the spectrum of command, control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR) technologies and capabilities that address communications challenges related to national defense, homeland security, disaster response and interoperability...
The Network Connectivity Analysis Model (NCAM) is a general purpose radio frequency (RF) event-based simulator that addresses the physical layer of the International Organization for Standards (IOS) Open System Interconnect (OSI) 7-layer model for wireless communication systems. With a modular design hierarchically organized to emulate an actual physical test setup, NCAM provides the U.S. Army with...
This paper proposes silence drop first algorithm(SDF) for the active buffer management. This algorithm finds and drops silence packet rather than talkspurt packet in the queue for resolving buffer overflow of queue. This algorithm can serve more simultaneous user while maintain voice service quality with same link capacity. Simulations with voice codec of G.711 and G.729a are performed in this paper...
Two X/Ka tri-band reflector antennas (Large X/Ka and Small X/Ka), have been designed, fabricated, and tested successfully for the Navy Multiband Terminal (NMT) program. Both systems have gone through DVT tests with excellent performance and several EDM units have been delivered. Key challenges of the design are presented, including a compact tri-band feed with low axial ratio, reflector optics with...
In this paper a novel technique for implementing heavily bit error protected 8 and 12 kilobits per second (kbps) voice coder (vocoder) based on a 2.4 kbps vocoder specified in Tactical Secure Voice Cryptographic Interoperability Specification (TSVCIS) is compared to the current 16 kbps Continuously Variable Slope Delta Modulation (CVSD) used in several legacy military radios and the Single Channel...
With the appeal of smart phones and tablets on the battlefield, the One Force Tactical Communications System (OFTCS), a hybrid cellular-tactical network solution by Raytheon, enabled networked video and mission command services to the Tactical Edge at the Army Expeditionary Warfighter Experiment Spiral G. Using commercial mobile computing devices communicating on the OFTCS network, small unit leaders...
This paper presents an efficient scheme for a two-dimensional (2-D) direction of arrival angle estimation (DOA) for multiple incident sources in the presence of coherent signals. A new antenna array configuration and innovative signal processing technique are presented. Compared with the well-known classical subspace schemes such as MUSIC and ESPRIT, the proposed method has several advantages. First,...
Real-time forensic reconstruction of a processes memory and interaction history is impractical in modern computing environments because the volume of data processed by a typical server is immense. Having this information would speed the search for zero-day exploits and designate precisely which system components could have been affected by an intrusion. Unfortunately, it may be several months after...
For multiple-input multiple-output (MIMO) systems, the optimum maximum likelihood (ML) detection requires tremendous complexity as the number of antennas or modulation level increases. This paper proposes a new algorithm which attains the ML performance with significantly reduced complexity. The proposed scheme is based on combining Branch and Bound algorithm (which solves an integer quadratic programming...
A noncooperative amplify-and-forward (AF) wireless relay network consisting of a one-source-one-destination pair and N relays is investigated. The objective of this paper is to analytically derive the explicit optimal noncooperative relay amplifying matrices (or vector) under both jamming and no-jamming environments, with the relay power constraint based on the minimum mean square error (MMSE) criterion...
Recent hardware advances allow more signal processing functionality to be integrated into a single chip. In sensor networks, the wireless nodes are typically operated with small batteries for which their replacement, when not impossible, is very difficult and expensive. Thus, minimizing the energy consumption of transmitting sensor nodes is an important issue on the design of such communication systems...
In this paper, we propose a new spatial-temporal joint sparsity method for the identification and detection of chemical plume in hyperspectral imagery. The proposed algorithm relies on two key observations: 1. each hyperspectral pixel can be approximately represented by a sparse linear combination of the training samples; and 2. neighborhood pixels from the same hyperspectral image as well as consecutive...
As high definition (HD) sensors on aerial Intelligence Surveillance Reconnaissance (ISR) platforms continue to be deployed, the appetite for high definition video transport and dissemination has been increasing rapidly. HD video is allowing analysts to achieve a level of detailed exploitation that was previously unimaginable with low-resolution full-motion video (FMV). Missions requiring targeting...
The problem of distributed detection of a noncooperative target with non-coherent binary observations is considered. The propagation is assumed to be inversely proportional to a power of the distance from the target and the signal is assumed to be subject to Rayleigh fading and additive white Gaussian noise (AWGN). As the location and power of the target are unknown, the probability of detection and...
Optical inter-satellite communication has been verified in-orbit. Between two LEO satellites bit error rates better than 10−11 at a data rate of 5.625 Gbps are achieved. Optical LEO-to-ground and ground-to-LEO links have been demonstrated. For the first time ESA will apply optical communication for operational services. The LEO-to-GEO link of a GEO relay, EDRS, the European data relay system, shall...
The adversarial agents problem is a generalized game-theoretic problem in which a set of agents faces a set of adversarial agents of varying types and capabilities, and must plan and perform actions to try to accomplish a specified goal; instances of this problem are often conceived as military combat situations. In this paper, we formulate the general adversarial agents problem as a non-linear integer...
The problem of quickly detecting a statistical change and identifying the change source is considered. In the problem studied, there are multiple sensors. A change can first occur at any one of these sensors and propagate to other sensors. One is required to detect the presence of such change with a minimal delay and furthermore identify the sensor that first observes the change. Three performance...
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