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Topic Review
Side Lobe
In antenna engineering, side lobes or sidelobes are the lobes (local maxima) of the far field radiation pattern of an antenna or other radiation source, that are not the main lobe. The radiation pattern of most antennas shows a pattern of "lobes" at various angles, directions where the radiated signal strength reaches a maximum, separated by "nulls", angles at which the radiated signal strength falls to zero. This can be viewed as the diffraction pattern of the antenna. In a directional antenna in which the objective is to emit the radio waves in one direction, the lobe in that direction is designed to have a larger field strength than the others; this is the "main lobe". The other lobes are called "side lobes", and usually represent unwanted radiation in undesired directions. The side lobe directly behind the main lobe is called the back lobe. The longer the antenna relative to the radio wavelength, the more lobes its radiation pattern has. In transmitting antennas, excessive side lobe radiation wastes energy and may cause interference to other equipment. Another disadvantage is that confidential information may be picked up by unintended receivers. In receiving antennas, side lobes may pick up interfering signals, and increase the noise level in the receiver. The power density in the side lobes is generally much less than that in the main beam. It is generally desirable to minimize the sidelobe level (SLL), which is measured in decibels relative to the peak of the main beam. The main lobe and side lobes occur for both transmitting and receiving. The concepts of main and side lobes, radiation pattern, aperture shapes, and aperture weighting, apply to optics (another branch of electromagnetics) and in acoustics fields such as loudspeaker and sonar design, as well as antenna design. Because an antenna's far field radiation pattern is a Fourier Transform of its aperture distribution, most antennas will generally have sidelobes, unless the aperture distribution is a Gaussian, or if the antenna is so small as to have no sidelobes in the visible space. Larger antennas have narrower main beams, as well as narrower sidelobes. Hence, larger antennas have more sidelobes in the visible space (as the antenna size is increased, sidelobes move from the evanescent space to the visible space).
  • 2.9K
  • 28 Nov 2022
Topic Review
AKG
AKG Acoustics (originally Akustische und Kino-Geräte Gesellschaft m.b.H., English: Acoustic and Cinema Equipment L.L.C.) is an acoustics engineering and manufacturing company. It was founded in 1947 by Dr. Rudolf Görike and Ernest Plass in Vienna, Austria. It is a part of Harman International Industries, a subsidiary of Samsung Electronics. The products currently marketed under the AKG brand mostly consist of microphones, headphones, wireless audio systems and related accessories for professional and consumer markets.
  • 2.9K
  • 20 Oct 2022
Topic Review
IoT and the Energy Sector
Integration of renewable energy and optimization of energy use are key enablers of sustainable energy transitions and mitigating climate change. Modern technologies such the Internet of Things (IoT) offer a wide number of applications in the energy sector, i.e, in energy supply, transmission and distribution, and demand. IoT can be employed for improving energy efficiency, increasing the share of renewable energy, and reducing environmental impacts of the energy use.
  • 2.9K
  • 26 Sep 2021
Topic Review
Emergency Communication Networks
Emergency communication refers to the communication means and methods needed for the extensive use of various communication resources to support rescues, including emergency rescues, and the necessary communication in the case of natural or manufactured emergencies. Because of the characteristics of disasters, making effective use of limited resources to provide the best communication services is a key problem. Unlike the traditional communication network, the emergency communication network is a complex network, and enables the implementation of emergency rescue activities and provides the primary conditions for the realization of emergency rescue functions. Its network structure has a significant impact on rescue efficiency. In different emergency situations, the demand for emergency communication is different, and the technical means used are different. Emergency communication mainly has the following characteristics: uncertainty of time and place; uncertainty of capacity demand; high degree of timeliness of the emergency communication; complexity of the environment; uncertainty of the degree of damage to the communication network itself; and diversification of information.
  • 2.9K
  • 24 Mar 2023
Topic Review
Actor
An actor or actress is a person who portrays a character in a performance. The actor performs "in the flesh" in the traditional medium of the theatre or in modern media such as film, radio, and television. The analogous Greek term is ὑποκριτής (Script error: No such module "Ancient Greek".), literally "one who answers". The actor's interpretation of a role—the art of acting—pertains to the role played, whether based on a real person or fictional character. This can also be considered an "actor's role," which was called this due to scrolls being used in the theaters. Interpretation occurs even when the actor is "playing themselves", as in some forms of experimental performance art. Formerly, in Ancient Greece and the medieval world, and in England at the time of William Shakespeare, only men could become actors, and women's roles were generally played by men or boys. While Ancient Rome did allow female stage performers, only a small minority of them were given speaking parts. The commedia dell’arte of Italy, however, allowed professional women to perform early on; Lucrezia Di Siena, whose name is on a contract of actors from 10 October 1564, has been referred to as the first Italian actress known by name, with Vincenza Armani and Barbara Flaminia as the first primadonnas and the first well-documented actresses in Italy (and in Europe). After the English Restoration of 1660, women began to appear onstage in England. In modern times, particularly in pantomime and some operas, women occasionally play the roles of boys or young men.
  • 2.8K
  • 02 Oct 2022
Topic Review
From 5G to 6G
As the deployment of 5G mobile radio networks gains momentum across the globe, the wireless research community is already planning the successor of 5G.
  • 2.7K
  • 29 Apr 2022
Topic Review
Vulnerabilities and Challenges in IoT-Enabled Smart Grids
Internet of Things (IoT) has appeared as one of the enabling technologies for smart energy grids by delivering abundant cutting-edge solutions in various domains, including critical infrastructures. As IoT-enabled devices continue to flourish, one of the major challenges is security issues, since IoT devices are connected through the Internet, thus making the smart grids vulnerable to a diverse range of cyberattacks. 
  • 2.7K
  • 25 Oct 2022
Topic Review
Power Domain-NOMA
In the current era of exponentially growing demand for user connectivity, spectral efficiency (SE), and high throughput, the performance goals have become even more challenging in ultra-dense 5G networks. The conventional orthogonal frequency division multiple access (OFDMA) tech-niques are mature but have not proven sufficient to address the growing user demand for high data rates and increased capacity. Therefore, to achieve an improved throughput in an ultra-dense 5G network with an expanded network capacity, the unified non-orthogonal multiple access (NOMA) technique is considered to be a more promising and effective solution. Throughput can be im-proved by implementing PD-NOMA, as the interference is managed with the successive inter-ference cancellation (SIC) technique, but the issue of increased complexity and capacity with compromised data rate persists.
  • 2.7K
  • 30 May 2022
Topic Review
Handover Management for Drone Networks
The drone, also known as an Unmanned Aerial Vehicle (UAV), is an autonomously flying aircraft controlled by an individual. The terms drone and UAV are used interchangeably here. Drones have attracted extensive attention for their environmental, civil, and military applications. Because of their low cost and flexibility in deployment, drones with communication capabilities are expected to play key important roles in Fifth Generation (5G), Sixth Generation (6G) mobile networks, and beyond. 6G and 5G are intended to be a full-coverage network capable of providing ubiquitous connections for space, air, ground, and underwater applications.
  • 2.7K
  • 08 Sep 2022
Topic Review
Dynamic Packet Duplication for Industrial URLLC
The fifth-generation (5G) network is presented as one of the main options for Industry 4.0 connectivity. To comply with critical messages, 5G offers the Ultra-Reliable and Low latency Communications (URLLC) service category with a millisecond end-to-end delay and reduced probability of failure. There are several approaches to achieve these requirements; however, these come at a cost in terms of redundancy, particularly the solutions based on multi-connectivity, such as Packet Duplication (PD). Specifically, this entry proposes a Machine Learning (ML) method to predict whether PD is required at a specific data transmission to successfully send a URLLC message. This entry is focused on reducing the resource usage with respect to pure static PD. 
  • 2.6K
  • 25 Jan 2022
Topic Review
Long Shot
In photography, filmmaking and video production, a long shot (sometimes referred to as a full shot or wide shot) typically shows the entire object or human figure and is usually intended to place it in some relation to its surroundings. These are typically shot now using wide-angle lenses (an approximately 25 mm lens in 35 mm photography and 10 mm lens in 16 mm photography). However, due to sheer distance, establishing shots and extremely wide shots can use almost any camera type.
  • 2.6K
  • 14 Oct 2022
Topic Review
Voice-Tacking
Voice-tracking, also called cyber jocking and referred to sometimes colloquially as a robojock, is a technique employed by some radio stations in radio broadcasting to produce the illusion of a live disc jockey or announcer sitting in the radio studios of the station when one is not actually present. It is one of the notable effects of radio homogenization.
  • 2.5K
  • 18 Oct 2022
Topic Review
Narrowband Internet of Things
Narrowband Internet of Things (NB-IoT) is one of the low-power wide-area network (LPWAN) technologies that aim to support enormous connections, featuring wide-area coverage, low power consumption, and low costs. NB-IoT could serve a massive number of IoT devices, but with very limited radio resources. Therefore, how to enable a massive number of IoT devices to transmit messages periodically, and with low latency, according to transmission requirements, has become the most crucial issue of NB-IoT.
  • 2.5K
  • 28 Apr 2022
Topic Review
AI Mk. VIII Radar
Radar, Airborne Interception, Mark VIII, or AI Mk. VIII for short, was the first operational microwave-frequency air-to-air radar. It was used by Royal Air Force night fighters from late 1941 until the end of World War II. The basic concept, using a moving parabolic antenna to search for targets and track them accurately, remained in use by most airborne radars well into the 1980s. Low-level development began in 1939 but was greatly sped after the introduction of the cavity magnetron in early 1940. This operated at 9.1 cm wavelength (3 GHz), much shorter than the 1.5 m wavelength of the earlier AI Mk. IV. Shorter wavelengths allowed it to use smaller and much more directional antennas. Mk. IV was blinded by the reflections off the ground from its wide broadcast pattern, which made it impossible to see targets flying at low altitudes. Mk. VIII could avoid this by keeping the antenna pointed upward, allowing it to see any aircraft at or above the horizon. The design was just beginning to mature in late 1941 when the Luftwaffe began low-level attacks. A prototype version, the Mk. VII, entered service on the Bristol Beaufighter in November 1941. A small number of these were sent to units across the UK to provide coverage at low altitudes while Mk. IV equipped aircraft operated at higher altitudes. After a small run of the improved Mk. VIIIA, the definitive Mk. VIII arrived in early 1942, offering higher power as well as a host of electronic and packaging upgrades. It arrived just as production rates of the De Havilland Mosquito began to improve, quickly displacing the Beaufighter units in RAF squadrons. Mk. VIII equipped Mosquitoes would be the premier night fighter from 1943 through the rest of the war. The Mk. VIII spawned a number of variants, notably the AI Mk. IX which included a lock-on feature to ease interceptions. A series of events, including a deadly friendly fire incident, so greatly delayed the Mk. IX that it never entered service. During the late-war period, many UK aircraft adopted the US SCR-720 under the name AI Mk. X. This worked on the same general principles as the Mk. VIII, but used a different display system that offered several advantages. Development of the basic system continued, and the Mk. IX would eventually briefly re-appear in greatly advanced form as the AI.17 during the 1950s.
  • 2.4K
  • 16 Nov 2022
Topic Review
Apple Bandai Pippin
The Apple Bandai Pippin, stylized PiP P!N, is a multimedia technology console, designed by Apple Computer. The console is based on the Apple Pippin platform – a derivative of the Apple Macintosh platform. Bandai produced the ATMARK and @WORLD consoles between 1996 and 1997. It was sold at $599. The goal of the Bandai Pippin was to create an inexpensive computer system aimed mostly at playing CD-based multimedia software, especially games, but also functioning as a thin client. The operating system is a version of System 7.5.2, and is based on a 66 MHz PowerPC 603 processor and a 14.4 kb/s modem. It features a 4×-speed CD-ROM drive and a video output that can connect to a standard television display.
  • 2.4K
  • 27 Oct 2022
Topic Review
Intelligent Buildings in Smart Grids
During the last decade, the smart grid (SG) concept has started to become a reality, mainly thanks to the technical progress achieved in telecommunications, informatics and power electronics, among other domains, leading to an evolution of the traditional electrical grid into an intelligent one. Nowadays, the SG can be seen as a system of smart systems that include cyber and physical parts from different technologies that interact with each other. In this context, intelligent buildings (IBs) constitute a paradigm in which such smart systems are able to guarantee the comfort of residents while ensuring an appropriate tradeoff of energy production and consumption by means of an energy management system (EMS).
  • 2.4K
  • 08 Jun 2021
Topic Review
Billing (Performing Arts)
Billing is a performing arts term used in referring to the order and other aspects of how credits are presented for plays, films, television, or other creative works. Information given in billing usually consists of the companies, actors, directors, producers, and other crew members.
  • 2.4K
  • 14 Oct 2022
Topic Review
Television Network
A television network or broadcaster is a telecommunications network for distribution of television program content, whereby a central operation provides programming to many television stations or pay television providers. Until the mid-1980s, television programming in most countries of the world was dominated by a small number of terrestrial networks. Many early television networks (such as the BBC, NBC or CBC) evolved from earlier radio networks.
  • 2.3K
  • 01 Nov 2022
Topic Review
6G Enabled Smart Infrastructure
6G is expected to have data rates in the order of terabits per second and a latency of less than 1ms. It is expected to drive the Internet of Everything, with 10,000,000 connections per square km.
  • 2.3K
  • 20 Apr 2021
Topic Review
Fault Tolerance Structures in Wireless Sensor Networks (WSNs)
The Industrial Revolution 4.0 (IR 4.0) has drastically impacted how the world operates. The Internet of Things (IoT), encompassed significantly by the Wireless Sensor Networks (WSNs), is an important subsection component of the IR 4.0. WSNs are a good demonstration of an ambient intelligence vision, in which the environment becomes intelligent and aware of its surroundings. WSN has unique features which create its own distinct network attributes and is deployed widely for critical real-time applications that require stringent prerequisites when dealing with faults to ensure the avoidance and tolerance management of catastrophic outcomes. Thus, the respective underlying Fault Tolerance (FT) structure is a critical requirement that needs to be considered when designing any algorithm in WSNs. Moreover, with the exponential evolution of IoT systems, substantial enhancements of current FT mechanisms will ensure that the system constantly provides high network reliability and integrity. 
  • 2.3K
  • 26 Aug 2022
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