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At least 19 records

Tunable Dielectric Materials and Devices for Broadband Wireless Communications

Wireless and satellite communications are a rapidly growing industries which are slated for explosive growth into emerging countries as well as countries with advanced economies. The dominant trend in wireless communication systems is towards broadband applications such as multimedia file transfer, video transmission and Internet access. These applications require much higher data transmission rates than those currently used for voice transmission applications. To achieve these higher data rates, substantially larger bandwidths and higher carrier frequencies are required. A key roadblock to implementing these systems at K-band (18-26.5 GHz) and Ka-band (26.5-40 GHz) is the need to develop hardware which meets the requirements for high data rate transmission in a cost effective manner. In this chapter, we report on the status of tunable dielectric thin films for devices, such as resonators, filters, phased array antennas, and tunable oscillators, which utilize nonlinear tuning in the control elements. Paraelectric materials such as Barium Strontium Titanate ((Ba, Sr)TiO3) have dielectric constants which can be tuned by varying the magnitude of the electric field across the material. Therefore, these materials can be used to control the frequency and/or phase response of various devices such as electronically steerable phased array antennas, oscillators, and filters. Currently, tunable dielectric devices are being developed for applications which require high tunability, low loss, and good RF power-handling capabilities at microwave and millimeter-wave frequencies. These properties are strongly impacted by film microstructure and device design, and considerable developmental work is still required. However, in the last several years enormous progress has occurred in this field, validating the potential of tunable dielectric technology for broadband wireless communication applications. In this chapter we summarize how film processing techniques, microwave test configurations, and prototype devices have combined to drive the field to its current stage of development.

Mueller, Carl H.↗

Communications interface for wireless communications headset

A universal interface adapter circuit interfaces, for example, a wireless communications headset with any type of communications system, including those that require push-to-talk (PTT) signaling. The interface adapter is comprised of several main components, including an RF signaling receiver, a microcontroller and associated circuitry for decoding and processing the received signals, and programmable impedance matching and line interfacing circuitry for interfacing a wireless communications headset system base to a communications system. A signaling transmitter, which is preferably portable (e.g., handheld), is employed by the wireless headset user to send signals to the signaling receiver. In an embodiment of the invention directed specifically to push-to-talk (PTT) signaling, the wireless headset user presses a button on the signaling transmitter when they wish to speak. This sends a signal to the microcontroller which decodes the signal and recognizes the signal as being a PTT request. In response, the microcontroller generates a control signal that closes a switch to complete a voice connection between the headset system base and the communications system so that the user can communicate with the communications system. With this arrangement, the wireless headset can be interfaced to any communications system that requires PTT signaling, without modification of the headset device. In addition, the interface adapter can also be configured to respond to or deliver any other types of signals, such as dual-tone-multiple-frequency (DTMF) tones, and on/off hook signals. The present invention is also scalable, and permits multiple wireless users to operate independently in the same environment through use of a plurality of the interface adapters.

Seibert, Marc A.↗

Helical antenna and method of modulating the performance of a wireless communications device

A wireless communication device includes an array of helical antennas on a substrate. Each helical antenna comprises a strain-relieved sheet with a conductive strip thereon, where the strain-relieved sheet and the conductive strip are in a rolled configuration about a longitudinal axis. The conductive strip is oriented at an angle α with respect to a rolling direction so as to comprise a helical configuration about the longitudinal axis with a non-zero helix angle β. The array exhibits a maximum gain of at least about 10 dB at a working frequency of at least about 0.1 THz.

Li, Xiuling↗

Devices, base stations, and methods for communicating scheduling requests via an underlay control channel in a wireless communication system

Wireless communication systems, base stations, and user equipment are disclosed that enable communication of scheduling requests via an underlay control channel that has an energy below a noise level of the spectrum. The scheduling requests may be sent and received at any time, including during downlink and uplink data communication periods of the base station.

42 ENGINEERING↗

NASA Bluetooth Wireless Communications

NASA has been interested in wireless communications for many years, especially when the crew size of the International Space Station (ISS) was reduced to two members. NASA began a study to find ways to improve crew efficiency to make sure the ISS could be maintained with limited crew capacity and still be a valuable research testbed in Low-Earth Orbit (LEO). Currently the ISS audio system requires astronauts to be tethered to the audio system, specifically a device called the Audio Terminal Unit (ATU). Wireless communications would remove the tether and allow astronauts to freely float from experiment to experiment without having to worry about moving and reconnecting the associated cabling or finding the space equivalent of an extension cord. A wireless communication system would also improve safety and reduce system susceptibility to Electromagnetic Interference (EMI). Safety would be improved because a crewmember could quickly escape a fire while maintaining communications with the ground and other crewmembers at any location. In addition, it would allow the crew to overcome the volume limitations of the ISS ATU. This is especially important to the Portable Breathing Apparatus (PBA). The next generation of space vehicles and habitats also demand wireless attention. Orion will carry up to six crewmembers in a relatively small cabin. Yet, wireless could become a driving factor to reduce launch weight and increase habitable volume. Six crewmembers, each tethered to a panel, could result in a wiring mess even in nominal operations. In addition to Orion, research is being conducted to determine if Bluetooth is appropriate for Lunar Habitat applications.

Miller, Robert D.↗

Device and method for detecting presence of a wireless communication device

A device and method for detecting presence of a wireless communication device having an antenna with intrinsic characteristics includes a transmitter, a receiver, a memory element, and a processing element. The transmitter may send a first signal to the antenna of the wireless communication device. The receiver may receive a second signal from the antenna of the wireless communication device, the second signal being a first portion of the first signal that is reflected by the antenna based on intrinsic characteristics of the antenna. The memory element may store intrinsic characteristic information for the antenna. The processing element may determine presence of the wireless communication device by analyzing the second signal against the intrinsic characteristic information stored in the memory element.

Allnutt, Daniel↗

Terabit Wireless Communication Challenges

This presentation briefly discusses a research effort on Terabit Wireless communication systems for possible space applications. Recently, terahertz (THz) technology (300-3000 GHz frequency) has attracted a great deal of interest from academia and industry. This is due to a number of interesting features of THz waves, including the nearly unlimited bandwidths available, and the non-ionizing radiation nature which does not damage human tissues and DNA with minimum health threat. Also, as millimeter-wave communication systems mature, the focus of research is, naturally, moving to the THz range. Many scientists regard THz as the last great frontier of the electromagnetic spectrum, but finding new applications outside the traditional niches of radio astronomy, Earth and planetary remote sensing, and molecular spectroscopy particularly in biomedical imaging and wireless communications has been relatively slow. Radiologists find this area of study so attractive because t-rays are non-ionizing, which suggests no harm is done to tissue or DNA. They also offer the possibility of performing spectroscopic measurements over a very wide frequency range, and can even capture signatures from liquids and solids. According to Shannon theory, the broad bandwidth of the THz frequency bands can be used for terabit-per-second (Tb/s) wireless communication systems. This enables several new applications, such as cell phones with 360 degrees autostereoscopic displays, optic-fiber replacement, and wireless Tb/s file transferring. Although THz technology could satisfy the demand for an extremely high data rate, a number of technical challenges need to be overcome before its development. This presentation provides an overview the state-of-the- art in THz wireless communication and the technical challenges for an emerging application in Terabit wireless systems. The main issue for THz wave propagation is the high atmospheric attenuation, which is dominated by water vapor absorption in the THz frequency band. The technical challenges in design such a system and the techniques to overcome the challenges will be discussed in this presentation.

Hwu, Shian U.↗

Roundtable Report: Terahertz and 6G Wireless Communications in Science and Extreme Environments

The main objective of the roundtable is to bring together computer scientists and wireless communications experts from industry, academia, and government to explore the electromagnetic spectrum in the Terahertz (THz) bands for ultra-high-speed short-distance wireless communications in extreme environments. This new generation of THz wireless communications is the key to future machine-to-machine communications critical for the mass deployment of an intelligent Internet of Things (IoT). The roundtable discussion explores THz and 6G wireless technologies along with Visible Light Communications (VLC), intelligent reflection surfaces, free-space quantum and optical communications, and nano communications. The roundtable considers the suitability of these technologies for extreme environments from the nanoscale to the mesoscale for the following: scientific facilities and associated instruments, as well as industry, and manufacturing. Such use cases are not traditionally the primary customer of commercial wireless networks which are focused on personal broadband voice and data communications. Finally, the discussion identifies high-level opportunities and challenges for leveraging THz and 6G wireless communications and related Artificial Intelligence (AI) that can catalyze the advancement of the development of hyperconnected smart scientific instruments and facilities.

97 MATHEMATICS AND COMPUTING↗

Emulation Platform for Cyber Analysis of Wireless Communication Network Protocols

Wireless networking and mobile communications is increasing around the world and in all sectors of our lives. With increasing use, the density and complexity of the systems increase with more base stations and advanced protocols to enable higher data throughputs. The security of data transported over wireless networks must also evolve with the advances in technologies enabling more capable wireless networks. However, means for analysis of the effectiveness of security approaches and implementations used on wireless networks are lacking. More specifically a capability to analyze the lower-layer protocols (i.e., Link and Physical layers) is a major challenge. An analysis approach that incorporates protocol implementations without the need for RF emissions is necessary. In this research paper several emulation tools and custom extensions that enable an analysis platform to perform cyber security analysis of lower layer wireless networks is presented. A use case of a published exploit in the 802.11 (i.e., WiFi) protocol family is provided to demonstrate the effectiveness of the described emulation platform.

97 MATHEMATICS AND COMPUTING↗

Monitoring devices and systems for monitoring frequency hopping wireless communications, and related methods

Monitoring devices and systems comprise a plurality of data channel modules coupled to processing circuitry. Each data channel module of the plurality of data channel modules is configured to capture wireless communications for a selected frequency channel. The processing circuitry is configured to receive captured wireless communications from the plurality of data channel modules and to organize received wireless communications according to at least one parameter. Related methods of monitoring wireless communications are also disclosed.

42 ENGINEERING↗

Ultra-high reliability wireless communication systems and methods

Systems and methods for ultra-high reliability (UHR) wireless communications systems and methods are disclosed. The disclosed UHR wireless communications systems and methods make the networked components on a communications infrastructure robust to interference caused by unintentional jamming, intermittent connectivity, weather, and physical barriers.

Russell, John J.↗

Ultra-high reliability wireless communication systems and methods

Systems and methods for ultra-high reliability (UHR) wireless communications systems and methods are disclosed. The disclosed UHR wireless communications systems and methods make the networked components on a communications infrastructure robust to interference caused by unintentional jamming, intermittent connectivity, weather, and physical barriers.

Russell, John L.↗

A Low Cost Traveling Wave Tube for Wireless Communications

Demand for high data rate wireless communications is pushing up amplifier power, bandwidth and frequency requirements. Some systems are using vacuum electron devices again because solid-state power amplifiers are not able to efficiently meet the new requirements. The traveling wave tube is the VED of choice because of its excellent broadband capability as well as high power efficiency and frequency. But TWTs are very expensive on a per watt basis below about 200 watts of output power. We propose a new traveling wave tube that utilizes cathode ray tube construction technology and electrostatic focusing. We believe the tube can be built in quantity for under $1,000 each. We discuss several traveling wave tube slow wave circuits that lend themselves to the new construction. We will present modeling results and data on prototype devices.

Vancil, Bernard Kenneth↗

SBIR Phase II Final Report - A Robust Wireless Communication System for Harsh Environments Including Nuclear Facilities

This is the Final Report for the DOE Phase II SBIR project “A Robust Wireless Communication System for Harsh Environments Including Nuclear Facilities.” The topics covered herein include technical progress made, progress against the planned milestones and deliverables, project outcomes, and a discussion on future expectations of deployment and impacts of the results of this work. In brief, all planned work for the project was successfully completed, on or ahead of schedule and on budget. The major accomplishment was the successful development of new sensor/communications systems with wideband (WB)/ultra-wideband (UWB) communications based on the software-defined-radio (SDR) technology to improve sensing and control in nuclear power plants and then a broad range of similar sensing applications. The impacts of these disciplines/focuses of this SBIR include: A new multi-frequency SDR-based architecture with WB/UWB communications integrated with sensors was developed, utilizing 310 MHz, 450 MHz, 915 MHz, and 5 GHz frequencies; Secure communications using Advanced Encryption Standard (AES) algorithm; Sensing possibilities not effectively addressed by previous technologies was addressed; and, The newly developed wireless sensor communications system can adapt its communications parameters to its operational environment for optimal performance. The performance of this system has been evaluated by systematic laboratory and field testing. The field testing was conducted at Massachusetts Institute of Technology (MIT)’s Nuclear Test Reactor, and the McClellan Nuclear center at the University of California Davis (UC Davis), as well as at Oak Ridge National Laboratory (ORNL). The success in this project resulted in DSI being awarded “The DOE’s 2018 SBIR/STTR Small Business of the Year”. This technology has attracted interest from The Rolls Royce company with ongoing discussions under NDA for potential strategic partnership between DSI and Rolls Royce in providing wireless sensor communications in nuclear facilities. Furthermore, the success of this project has attracted significant interest from the United Nations International Atomic Agency (IAEA) in Vienna, Austria, as well as other DOE and DOD offices. Currently, per request from IAEA, DOE’s office of International Safeguards has funded DSI to develop a WB/UWB wireless communication system for real-time transmission of images from IAEA’s safeguards cameras in various nuclear facilities. DSI also has received a Phase II and Phase II.5 SBIR awards from ARMY and NAVY for wireless communications capability for various DOD aircraft.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

High Temperature Wireless Communication And Electronics For Harsh Environment Applications

In order for future aerospace propulsion systems to meet the increasing requirements for decreased maintenance, improved capability, and increased safety, the inclusion of intelligence into the propulsion system design and operation becomes necessary. These propulsion systems will have to incorporate technology that will monitor propulsion component conditions, analyze the incoming data, and modify operating parameters to optimize propulsion system operations. This implies the development of sensors, actuators, and electronics, with associated packaging, that will be able to operate under the harsh environments present in an engine. However, given the harsh environments inherent in propulsion systems, the development of engine-compatible electronics and sensors is not straightforward. The ability of a sensor system to operate in a given environment often depends as much on the technologies supporting the sensor element as the element itself. If the supporting technology cannot handle the application, then no matter how good the sensor is itself, the sensor system will fail. An example is high temperature environments where supporting technologies are often not capable of operation in engine conditions. Further, for every sensor going into an engine environment, i.e., for every new piece of hardware that improves the in-situ intelligence of the components, communication wires almost always must follow. The communication wires may be within or between parts, or from the engine to the controller. As more hardware is added, more wires, weight, complexity, and potential for unreliability is also introduced. Thus, wireless communication combined with in-situ processing of data would significantly improve the ability to include sensors into high temperature systems and thus lead toward more intelligent engine systems. NASA Glenn Research Center (GRC) is presently leading the development of electronics, communication systems, and sensors capable of prolonged stable operation in harsh 500C environments. This has included world record operation of SiC-based transistor technology (including packaging) that has demonstrated continuous electrical operation at 500C for over 2000 hours. Based on SiC electronics, development of high temperature wireless communication has been on-going. This work has concentrated on maturing the SiC electronic devices for communication purposes as well as the passive components such as resistors and capacitors needed to enable a high temperature wireless system. The objective is to eliminate wires associated with high temperature sensors which add weight to a vehicle and can be a cause of sensor unreliability. This paper discusses the development of SiC based electronics and wireless communications technology for harsh environment applications such as propulsion health management systems and in Venus missions. A brief overview of the future directions in sensor technology is given including maturing of near-room temperature "Lick and Stick" leak sensor technology for possible implementation in the Crew Launch Vehicle program. Then an overview of high temperature electronics and the development of high temperature communication systems is presented. The maturity of related technologies such as sensor and packaging will also be discussed. It is concluded that a significant component of efforts to improve the intelligence of harsh environment operating systems is the development and implementation of high temperature wireless technology

Hunter, G. W.↗

Spread spectrum scheduling requests for wireless communication resource

Apparatuses, systems and methods are disclosed for wireless communication. A base station may communicate with a plurality of user equipments (UEs) without allocating spectral resources to the UEs for communicating scheduling requests. The base station may detect a scheduling request from a requesting UE of the plurality of UEs. The scheduling request may include a spread spectrum signal based on a spreading sequence. The scheduling request may indicate an identity for a requesting UE without indicating information other than the identity. The base station may grant spectral resources to the requesting UE in response to detecting a scheduling request.

Moradi, Hussein↗

Compact mobile-reader system for two-way wireless communication, tracking and status monitoring for transport safety and security

A system for monitoring a plurality radio frequency identification tags is described. The system uses at least one set of radio frequency identification tags. Each tag is attached to a container and includes several sensors for detecting physical conditions of said container. The system includes at least one autonomous intermediate reader in wireless communication with the frequency identification tags. The intermediate reader includes external wireless communication system, intermediate reader logic controller, and a self-contained rechargeable power supply. The system uses a central status reporting system in communication the intermediate reader.

97 MATHEMATICS AND COMPUTING↗

Low-PAPR interleaved single-carrier FDM scheme for optical wireless communications

As a potential complementary access technology for the 5G wireless systems, optical wireless communication (OWC) gains extensive attention for decades owing to its numerous advantages of broad license-free spectrum, immunity to electromagnetic interference and high-level privacy. However, two rigorous obstacles to achieve high data-rate OWC transmission are the severe nonlinear clipping of transmitter and high-frequency attenuation of OWC system. In this paper, we propose the first interleaved single-carrier frequency-division multiplexing (I-SC-FDM) scheme for OWC systems. Compared with orthogonal frequency-division multiplexing (OFDM), I-SC-FDM has a lower peak-to-average power ratio, which makes it more immune to the nonlinearity clipping in OWC systems. Meanwhile, for the bandwidth-limited OWC systems, I-SC-FDM has better performance on resistance to the serious high-frequency distortion. The simulation results indicate that, under the transmitter nonlinearity and optical-wireless diffuse fading channel, the maximum Q{sup 2} of I-SC-FDM is about 3.44 dB and 3.14 dB higher than that of OFDM when 4-ary quadrature amplitude modulation (4-QAM) and 16-QAM are modulated, respectively. The results show the feasibility and advantages of I-SC-FDM for cost-sensitive OWC systems.

77 NANOSCIENCE AND NANOTECHNOLOGY↗