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Physical-layer network coding (PLNC) is a novel wireless communication technology, in which multiple transmitters can send signals on the same channel to the same receiver at the same time. Our previous studies have revealed that PLNC can substantially
Direct-sequence spread-spectrum underwater acoustic communications are analyzed in this paper between communication nodes, at least one of which is moving. At-sea data are analyzed which show that the phase change due to source motion is significant. The
We propose a non-coherent receiver for the fixed detect-and-forward relay channel and derive a closed-form tight upper bound on its bit error probability in Rayleigh fading channels. Using this upper bound, we show that the receiver achieves nearly full
This paper proposes a simple non-coherent amplify-and-forward receiver for the relay channel and evaluates its diversity performance for Rayleigh fading channels. We use the generalized likelihood ratio test to obtain the decision rule in closed form
The main benefit of vehicular communication is seen in active safety systems that increase passenger safety by exchanging warning messages between vehicles. Other applications and private services are also permitted in order to lower the cost and to
In most conventional layer 2 triggering approaches, a pre-defined threshold for a specific perspective such as the received signal strength is used. This may cause too late or too early handover executions. In this paper we propose a new predictive
Antonio Izquierdo Manzanares, Nada T. Golmie, Katrin Hoeper, Lidong Chen
In this paper we compare different authentication techniques that may be used in order to reduce the time and resources required to perform a handover, namely, re-authentication and pre-authentication. We provide a detailed analysis of each mechanism, and
[Superseded by SP 800-121 Rev. 1 (June 2012): http://www.nist.gov/manuscript-publication-search.cfm? pub_id=911133] Bluetooth is an open standard for short-range radio frequency communication. Bluetooth technology is used primarily to establish wireless
Phone managers are non-forensic software tools designed to carry out a range of tasks for the user, such as reading and updating the contents of a phone, using one or more of the communications protocols supported by the phone. Phone managers are sometimes
Catherine A. Remley, George Hough, Galen H. Koepke, Dennis G. Camell, Robert Johnk, Chriss A. Grosvenor
We report on propagation tests carried out in a subterranean tunnel to support improved wireless communications for urban search and rescue robots. We describe single-frequency and ultrawideband channel-characterization tests that we conducted, as well as
Christopher L. Holloway, Galen H. Koepke, Dennis G. Camell, Catherine A. Remley
We are investigating various schemes for detecting first responders and civilians with portable radios or cell phones who are trapped in voids in a collapsed or partially collapsed building. The first part of this effort is to understand propagation in
Christopher L. Holloway, William F. Young, Galen H. Koepke, Catherine A. Remley, Dennis G. Camell, Yann Becquet
In this report, we investigate radio communication problems faced by emergency responders (firefighters, police and emergency medical personnel) in disaster situations. A fundamental challenge to communications into and out of large buildings is the strong
Karen A. Scarfone, Derrick Dicoi, Matt Sexton, Cyrus Tibbs
The purpose of this document is to provide guidance to organizations in securing their legacy Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless local area networks (WLAN) that cannot use IEEE 802.11i. The document provides an
Chriss A. Grosvenor, David R. Novotny, Dennis G. Camell, Galen H. Koepke, Robert Johnk, Seturnino Canales
The National Institute of Standards and Technology has completed shielding effectiveness/penetration studies on three different aircraft types for the Federal Aviation Administration. The studies are used to understand the cavity coupling characteristics
Mohamed T. Refaei, Nader Moayeri, Michael R. Souryal
A common strategy for responding to indoor emergency scenarios is to rapidly deploy a group of first responders inside the incident area and an incident command center outside of the incident area. First responders are equipped with radios that allow them
Using cooperative transmission, two or more single-antenna users can share their antennas to achieve spatial diversity in a slow fading channel. One relaying protocol that achieves diversity, amplify-and-forward (AF), is striking in its simplicity, but
Howard C. Reader, Dylan Williams, Paul D. Hale, Tracy S. Clement
We characterize a 50 GHz comb generator measured on a sampling oscilloscope. With careful control of the input power, input harmonics and comb generator temperature, we find the output spectrum to be stable to 0.1 dB and 0.5 degrees. We correct results for
Michael R. Souryal, E G. Larsson, B M. Peric, B R. Vojcic
This paper derives new soft decision metrics for coded orthogonal signaling in impulsive noise, more specifically symmetric alpha-stable noise. For the case of a known channel amplitude and known noise dispersion, exact metrics are derived both for Cauchy
Karen A. Scarfone, Murugiah P. Souppaya, Matt Sexton
Many threats against end user devices, such as desktop and laptop computers, smart phones, personal digital assistants, and removable media, could cause information stored on the devices to be accessed by unauthorized parties. To prevent such disclosures
We have combined a commercially available, variable length coaxial delay line (trombone line) with a high resolution linear translation system. The result is better resolution and lower uncertainty in the achievable delays than previously available. The
Michael R. Souryal, Johannes Geissbuehler, Leonard E. Miller, Nader Moayeri
When the range of single-hop wireless communication is limited by distance or harsh radio propagation conditions, relays can be used to extend the communication range through multihop relaying. This paper targets the need in certain scenarios for rapid