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There is a dramatic increase in standards work due to the progress of cognitive radio technology and changes in spectrum allocation dictated by the Federal Communications Commission (FCC). The IEEE Standards Coordinating Committee 41 (SCC41) represents standards projects in the areas of dynamic spectrum access, cognitive radio, interference management, coordination of wireless systems, advanced spectrum...
This work proposes a method for localizing a single near-field source using a moving array. Using a phase correction factor calculated from two sequences of selected data snapshots, we extend the array aperture and compute the initial estimates of the source's bearing and range from the extended data sets. With the initial estimates of bearing and range we construct a phase difference factor to modify...
We present a new collision free medium access control algorithm suitable for large ad-hoc network. The algorithm is iterative and distributed, i.e., each node acquires, stores and processes only information related to its neighbors. Given a random set of nodes requesting access to the common medium during each timeslot, the algorithm attempts to allow the largest fraction of nodes to do so, subject...
Cooperative hybrid-ARQ (HARQ) protocols have been widely studied because they are more efficient than cooperative protocols without HARQ. In, the throughput of a cooperative HARQ protocol based on the decode-and-forward protocol (DF-HARQ) is obtained. In this paper, the maximum achievable throughput of the DF-HARQ protocol is obtained using the asymptotic outage probability when the maximum number...
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...
One of the fundamental differences between the terrestrial radio frequency (RF) signal and underwater acoustic signal is long propagation delay. This paper is focused on a scheduling scheme for regional data collection in underwater acoustic sensor networks. Long propagation delay of the acoustic signal causes a serious problem for transmission scheduling. In this paper, we propose an efficient transmission...
Telecommunication networks spanning large areas are subject to various failures. A survivable network provisioning scheme addressing multiple levels of network failures, especially disaster failures which may take out many network components, is desirable in the future Internet. In this study, we propose and investigate the characteristics of a multistate multipath provisioning scheme for telecom...
Tactical air-to-ground channels present a number of challenges for physical (PHY) layer waveform design including: (i) airborne platform dynamics (i.e., Doppler, frequency offset, jerk, etc.), (ii) benign to severe ground-level multipath, and (iii) partial to full blockage of the line-of-sight (LOS) path. Legacy military waveforms are not sufficiently robust to operate effectively in these severe...
This paper describes the high bandwidth high throughput (HBHT) government reference architecture (GRA) effort and utilization of dependency structure matrix (DSM) tools to validate the architecture. This paper is intended to show how the development of GRA compliant modules advances both new and time-tested technologies through establishing a standard for above 2 GHz SATCOM terminal modules. The paper...
A voice conversation quality over IP networks is mainly affected by the end-to-end delay and the packet-loss rate. Various delay channel environment can cause the early/late arrival packet loss without actual packet loss. To overcome time-variant dynamics of transmission channels for IP telephone services, an adaptive playout-buffer scheduling is proposed. Previous playout-buffer schedulers focused...
In this paper, we provide a feasibility analysis of non-contiguous orthogonal frequency division multiplexing (NC-OFDM) transceivers based on different operating configurations. The selection of these configurations conform to the constraints defined by the spectral masks of the Federal Communications Commission's (FCC), such as out-of-band radiation. Actual spectrum measurement data collected from...
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...
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...
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...
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...
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