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This document provides a concise overview of non-terrestrial network (NTN) technology from a 3GPP perspective. It explains that NTN in 5G includes various connection scenarios such as satellite-based communications and flight control of unmanned aerial vehicles. The document discusses the different network variations and studies conducted by 3GPP to enable NTN within the 5G system. It also highlights the use cases and spectrum aspects of NTN, as well as the relevant architectures for current and future NTN and satellite constellations. The goal of NTN is to provide global connectivity, particularly in underserved regions. The document also explores the characteristics and challenges of NTN in the context of 5G communications, including high-altitude platform systems (HAPS) and different NTN architectures. It addresses RF propagation aspects and challenges specific to NTN, such as path attenuation, round-trip time, Doppler frequency shift, and Faraday rotation. The document concludes by discussing the future evolution of wireless communications systems towards 6G. [Extracted from the article]

The article offers brief information on a new, compactsize broadband frequency synthesizer from AnaPico Switzerland, the QuEST tool from BSC Filters and coaxial circulators and isolators from CernexWave.

The article summarizes the findings of a research team from John Hopkins Applied Physics Laboratory in Laurel, Maryland, who studied how climate change could impact radio wave propagation and degrade defense technologies such as communication systems navigation and surveillance radars. It discusses the implications and recommendations for future defense acquisition and innovation efforts. Also mentioned is the discovery on the possible impact of higher temperatures and increased humidity.

The article offers information on Ka-band satellites which present numerous challenges as of March 2018 despite being around for years, highlighting the system impact of channel properties such as rain degradation. Topics include the components of Ka-band equipment, ways to mitigate the challenges that Ka-band satellites pose, and propagation losses. Also discussed are several properties of a comparative link budget related to system performance.

The article discusses the paths of the propagation of electromagnetic (EM) energy which is crucial for numerous radio frequency and microwave signal applications. It offers information on EM propagation which starts and ends with antennas such as dipoles and multiple antenna elements. Topics include the behavior of radiowaves, the importance of point source antenna in efficient EM propagation, and the use of millimeter waves.

The article informs that the U.S. Defense Advanced Research Project Agency (DARPA) develops Very Low Earth Orbit (VLEO) satellites to monitor ionosphere. It further discusses quantify space high frequency (HF) noise environment and improve characterization of the ionosphere to support warfighter capabilities; to map the constantly changing "terrain" of the ionosphere in real-time; and develop, qualify, launch and operate multiple small satellites carrying scientific & mission instrumentation.

The article informs that the Next-Generation Dagaie System (NGDS) Safran S.A. trainable decoy launcher has been selected to equip Canada's next generation surface combatant. It further discusses selection of the NGDS for the 15-ship Canadian Surface Combatant (CSC) program; request for information (RFI) for offboard electronic countermeasures (OB ECM) munitions for CSC; and Safran has subsequently introduced alternative barrel module configurations.

The article offer news briefs associated with the defence industry. Topics discussed include development of a new approach to defeat adversaries by BAE Systems as part of the Complexity Modeling in Multiple Domains program, Ionospheric Insights to Enhance High Frequency Radio Capabilities by Defense Advanced Research Projects Agency and installation of the first Global Aircrew Strategic Network Terminal system for the U.S. Air Force by Raytheon Intelligence & Space.

The article looks at the key issues encountered with test systems for millimeter wave (mmWave) frequencies. It explores market segments that are adopting mmWave frequencies, including 5G, automotive radar, and point-to-point links, along with their design and test considerations. Among of the challenges of higher frequency transmission, driven by advancement of mmWave technology, are higher propagation loss, measurement repeatability, and field testing.

The article focuses on describing the test challenges of the next generation, the fifth generation and testing of 5G at mmWave frequencies without cables. Topics include development of a 5G air interface that relies on beam-steered antennas at both ends of the link, details on radiated testing, and the test challenges in the area of performance testing in realistic radio environments.

The article discusses trial of Airbus and NTT DOCOMO, INC. to demonstrate the ability to use its solar-powered Zephyr High Altitude Platform Station (HAPS) to deliver future wireless broadband connectivity. It mentions Zephyr S provided an agile data link during a stratospheric flight to simulate future direct-to-device connectivity; and also mentions aims to provide communication services to mountainous areas, remote islands and maritime areas where radio waves have difficulty reaching.

The article presents the third part of a three-part series on transverse magnetic (TM) mode propagation. It offers practical applications for such mode along the surface of a single unconditioned conductor. It examines the characteristics of TM mode power-line systems. It explores the capabilities of the Radio Frequency/microwave transmission systems using the TM mode that have been dubbed E-line.

The article discusses the commercial implementation of Mobile WiMAX that uses smart antenna technologies such as multiple input/multiple output (MIMO) and beam forming. MIMO is based on the concept of multi-antenna arrays which are devised for both transmitter and receiver. It also uses multi-path propagation that doubles bandwidth capacity and efficiency of single frequency. Beam forming strengthens weak signals that enables transmission to be easier.

The article explores several radio propagation modes. It discusses cylindrical propagation which is used when propagation is impacted by a series of ridge lines, radio transmission through forested terrain where significant attenuation can arise and over water propagation involving a shore-based transmitter and a shipboard antenna.

The article offers information on several propagation modes for radio waves propagation. Among the modes discussed include the line of sight propagation (LOS) which comes from optics assuming the occurrence of propagation in clean environment, the two-ray propagation which plays an important role in very high frequency (VHF) and ultra high frequency communication links, and the Fresnel zone distance which caters the distance from the transmitter to the receiver.

Charts are presented depicting radio propagation over water including its distance as well as curves towards different heights of transmit antennas and very high frequency (VHF) maritime mobile radio services.

The article offers information on several conferences and exposition to be held in August 2019 which include Drive World Conference and ExpoAutoTestCon of Institute of Electrical and Electronics Engineers (IEEE) and RSM conference on photonics and sensor technology.

The article discusses the knife-edge diffraction (KED) concept in relation to propagation loss in the communications frequency bands. An illustration of the geometry of the link over a knife edge is presented. It is suggested that non-line-of-sight propagation over a mountain or ridge line is usually estimated as though it were propagation over a knife edge.

The article focuses on link losses between isotropic antennas used in electronic warfare (EW) communications. Widely used propagation models include the Okumura and Hata models which are intended for indoor propagation. It details the use of line of sight (LOS), two ray and knife edge diffraction propagation loss models. The mathematical procedure to determine the loss ratio through an LOS model is discussed.

Part III. Discusses commonly used radio propagation models and their normal applications. Focus on very high frequency and ultra-high frequency propagation; Consideration of losses related to link geometry; Suitability of free-space propagation models for propagation without significant reflection paths; Conditions for the occurrence of reflection paths; Two-ray propagation; Knife-edge propagation; Formulas.

Part 2. Discusses high-frequency radio propagation. Ionospheric reflection; High-frequency propagation path; Single-site locator operation.

The article reports on the use of finite-difference-time-domain (FDTD) techniques that can offer accurate results in modeling real-time propagation. It discusses the deployment of moving-window finite-difference-time-domain (MWFDTD) approach as an alternative to FDTD as it limited in space and requires computational resources. It states that the MWFDTD approach can be moved faster by using a graphics processor unit (GPU) to share and hasten calculations.

The article reports that Elektrobit Corp. has developed EB Propsim C8 propagation simulator equipped with the ASO tool to emulate the effects of fading, noise, velocity and acceleration on fast-moving communications signals. The tool can create the complex signal conditions needed to emulate communications channels in aerospace and airborne from 350 megahertz channel bandwidths. The EB Propsim C8 with ASO is available with optional internal interference generator to produce Gaussian noise.

The article reports on the study which focuses on the utilization of very-low-frequency (VLF) propagation in worldwide lightning location (WWLL). The VLF was distributed in the Earth-ionosphere-waveguide (EIWG) atmospheric layer to detect lightning signals globally. It reveals that the study was participated by several researchers, including Richard Dowden, Erin Lay and Neil Thomson.

The article presents a technical description of how a voltage waveform propagates without sensible degradation at a constant velocity without significant loss of amplitude. An L-C ladder model is provided to illustrate the behavior of a typical printed-circuit-board (PCB) transmission line from a digital application. Considering the difference between the voltage waveforms at different times, the article suggests that the properties of lossless propagation and resistive input impedance are inextricably linked. In addition, the input impedance may no longer appear purely resistive.

The article discusses research being done on two dimensional (2D) Luneberg lens. It references a study by Xidong Wu and Jean-Jacques Laurin published in the August 2007 issue of "IEEE Transactions on Antennas and Propagation." The proposed lens is based on a partially-filled parallel plate technique. The findings show broadband characteristics with radiation efficiencies between 43% and 72% over the tested frequency band of 26.5 to 37 Gigahertz (GHz).

A calendar of events related to electronics and communications for the year 2007 and 2008 is presented. The workshop entitled "Fourth International Workshop on Advanced Ground Penetrating Radar" will be held on June 27-29, 2007 in Naples, Italy. The International Symposium on Antennas and Propagation will be held on August 20-24, 2007 in Niigata, Japan. The IEEE MTT-S International Microwave Symposium and Exhibition will be held on June 15-20, 2008 in Atlanta, Georgia.

Comments on the of features of personal computer-board transmission lines. Propagation of the input signal; Association between a rope and transmission line; Observation on the pattern of wave propagation.