Wireless | Wikipedia audio article
Wireless. Communication. As the transfer, of information or, power between, two or more points, that are not connected, by an electrical, conductor, the. Most common, wireless, technologies. Use radio, waves with. Radio, waves distances. Can be short such as a few meters for Bluetooth or as far as millions, of kilometers, for deep space radio, communications. It. Encompasses. Various types. Of fixed mobile, and portable, applications. Including. Two-way, radios, cellular. Telephones, personal. Digital assistants. PDAs. And wireless. Networking, other. Examples. Of applications. Of radio wireless, technology. Include, GPS units. Garage, door openers, wireless. Computer, mouse keyboards. And headsets, headphones. Radio. Receivers. Satellite. Television, broadcast. Television and, cordless, telephones. Somewhat. Less common methods of achieving wireless. Communications. Include, the use of other electromagnetic. Wireless. Technologies. Such, as light magnetic. Or electric. Fields, or the use of sound. The. Term Wireless, has been used twice in communications. History, with slightly different meaning, it. Was initially used from about 1890, for, the first radio transmitting. And receiving technology. As in wireless, telegraphy, until, the new word radio replaced, it around 1920. The. Term was revived in the 1980s. And 1990s, mainly. To distinguish, digital, devices that, communicate without wires such, as the examples, listed in the previous paragraph from, those that require, wires or cables, this. Became, its primary usage, in the 2000s. Due to the advent, of technologies. Such as mobile broadband, Wi-Fi, and, Bluetooth. Wireless. Operations. Permit services, such, as mobile and interplanetary. Communications. That are impossible or, impractical to, implement, with the use of wires, the. Term is commonly used in the telecommunications. Industry to, refer to telecommunications. Systems, eg radio. Transmitters. And receivers remote. Controls etc which. Used some form of energy eg radio. Waves acoustic. Energy to, transfer information without, the use of wires. Information. Is transferred in this manner over both short and long distances. You. Topic. History. You. Topic. Photophone. The, first wireless, telephone, conversation. Occurred in 1880. When, Alexander. Graham Bell, and Charles, Sumner Tainter, invented, the photo phone a telephone, that sent idea over a beam of light, the. Photo phone required sunlight, to operate, and a clear line of sight between, transmitter, and receiver, these. Factors, greatly decreased, the viability, of the photo phone in any practical, use, it. Would be several decades, before the photo phone's principles, found their first practical, applications. In military, communications. And later in fiber-optic, communications. You. Topic. Electric. Wireless, technology. You. Topic. Early. Wireless. A number. Of wireless electrical. Signaling, schemes, including, sending electric. Currents, through water and the ground using, electrostatic. And electromagnetic, induction. Were, investigated. For telegraphy, in the late 19th, century before, practical. Radio systems, became, available. These. Included, a patented, induction, system by Thomas Edison allowing. A telegraph on a running train to connect with telegraph, wires running, parallel, to the tracks a william priests induction, telegraph, system, for sending messages across, bodies, of water and several, operational. And proposed telegraphy. And voice earth conduction. Systems. The. Edison system, was used by stranded, trains during the Great Blizzard of 1888, and. Earth conductive. Systems, found limited, use between trenches, during World War one but these systems were never successful. Economically. You. Topic. Radio. Waves. In, 1894. Ghuli Elmo Marconi, began developing. A wireless Telegraph. System, using, radio waves which, had been known about since proof of their existence, in 1888. By Heinrich. Hertz but, discounted, as a communication. Format, since they seemed at the time to be a short-range, phenomenon. Marconi. Soon developed, a system, that was transmitting, signals, way beyond distances. Anyone could have predicted due, in part to the signals, bouncing, of the then-unknown ionosphere. Marconi. And Karl Ferdinand, Braun were awarded, the 1909. Nobel, Prize for Physics for their contribution. To this form of wireless telegraphy. Millimeter. Wave communication. Was first investigated by, Jagadish, Chandra Bose during, 1894. To 1896. When he reached an extremely, high frequency of, up to 60, gigahertz in, his experiments. He also. Introduced, the use of semiconductor. Junctions, to detect, radio waves when, he patented the radio crystal, detector in 1901.
Topic. Wireless. Revolution. The, wireless, revolution began. In the 1990s. With the advent, of digital wireless, networks, leading, to a social, revolution and, a paradigm, shift from wired to wireless technology. Including. The proliferation, of commercial, wireless technologies. Such as cell phones mobile. Telephony pagers. Wireless. Computer, networks, cellular. Networks, the wireless, internet and laptop, and handheld, computers, with wireless, connections. The. Wireless, revolution has been driven by advances. In radio, frequency RF, and. Microwave, engineering. And the transition, from analog to digital RF. Technology which. Enabled, a substantial. Increase in voice traffic, along with the delivery, of digital, data such, as text, messaging, images. And streaming media the, core component, of this revolution. As the mosfet, metal-oxide-semiconductor. Field-effect. Transistor. Or MOS. Transistor. Power. MOSFETs. Such as LD m OS lateral. Diffuse, MOS. Are used in RF power, amplifiers. To boost RF signals, to a level that enables long-distance. Wireless, network, access for, consumers, while RF, CMOS Reggio frequency. CMOS, circuits. Are used in radio transceivers. To transmit, and receive wireless. Signals, at low cost and with low power consumption. The. MOSFET, as the basic, building block of modern wireless networks, including. Mobile networks, such as 2g. 3G. And 4G. Most. Of the essential, elements in modern wireless, networks, are built from MOSFETs, including. The base station, modules routers. RF, circuits, radio, transceivers. Transmitters. And RF, power amplifiers. MOSFET. Scaling, is also the primary factor. Behind rapidly. Increasing, wireless, network, bandwidth, which has been doubling, every 18 months, as noted, by Ed Holmes law the MOSFET, was invented, by Mohammed Attalla and dawan Kong at Bell Labs in, 1959. It's. Very large-scale integration. VLSI. Capability. Led to wide adoption for, digital, integrated, circuit, chips by the early, nineteen, 70s, but it was initially not, the most effective transistor. For analog, RF technology, where. The older bipolar, Junction, transistor, BJT, remained. Dominant up, until the 1980s. A, gradual. Shift began. With the emergence, of power MOSFETs. Which are discrete mos, power devices, designed for power electronic. Applications. Including. The vertical, power MOSFET, by Hitachi, in 1969. The VD mos, vertical. Diffuse, MOS. By John moles research, team at HP, Labs in. 1977. And the ldm, OS by Hitachi in. 1977. MOSFETs. Began, to be used for RF, applications in. The 1970s. RF. CMOS, which, are RF circuits, that use mixed, signal digital, and analog mos, integrated. Circuit technology and. Are fabricated. Using the CMOS, process, was later developed, by asada biddy at UCLA. In the late 1980s. By the early 1990s, the MOSFET, had replaced the BJT, as the core component, of RF technology leading. To a revolution. In wireless, technology. Power. MOSFET. Devices, particularly. The LD, MOS, became. The standard, RF, power amplifier. Technology. Which led to the development and, proliferation of, digital, wireless networks. RF. CMOS, integrated circuits. Also enabled, sophisticated. Low-cost, and portable, end user terminals, and gave rise to small low-cost. Low-power. And portable, units for a wide range of wireless communication. Systems. This. Enabled. Anytime. Anywhere. Communication. And helped bring about the wireless revolution leading. To the rapid growth of the wireless, industry. RF. CMOS, is used in the radio transceivers. Of all modern wireless networking, devices, and mobile phones and is widely used to transmit, and receive wireless. Signals, in a variety of applications. Such, as satellite, technology. Eg, GPS. Bluetooth, Wi-Fi. Near-field. Communication. NFC mobile. Networks, eg, 3G, and 4G, terrestrial. Broadcast, and automotive, radar, applications, among other uses, in. Recent, years an important, contribution, to the growth of wireless communication. Networks has been interference. Alignment which, was discovered, by Syed, Ali Jafar, at the University. Of California. Irvine. According. To Paul Horne this has revolutionized. Our. Understanding of. The capacity. Limits of wireless networks. And. Demonstrated. The astounding result, that each user in a wireless network can. Access half of the spectrum, without interference. From other users regardless. Of how many users are sharing the spectrum.
Topic. Modes. Wireless. Communications. Can be via. Topic. Radio. You. Radio. And. Microwave. Communication. Carry information, by modulating, properties, of electromagnetic, waves, transmitted. Through space. Topic. Freespace. Optical. Freespace. Optical, communication. FS, Oh is an optical, communication. Technology. That uses light propagating. In free space to transmit, wirelessly. Data for, telecommunications. Or computer, networking, free. Space, means. The light beams travel through the open air or outer space. This. Contrasts. With other communication. Technologies. That use light beams traveling, through transmission, lines such as optical fiber, or dielectric. Light. Pipes. The. Technology. Is useful where, physical, connections, are impractical due, to high costs, or other considerations. For. Example, freespace. Optical links. Are used in cities between office, buildings, which are not wired for networking where, the cost of running cable, through the building and under the street would be prohibitive. Another. Widely used example, as consumer, IR devices, such as remote controls, and era infrared. Data Association. Networking. Which is used as an alternative, to Wi-Fi, networking, to allow laptops. PDAs. Printers. And digital, cameras, to exchange data. You. Topic. Sonic. You. Sonic. Especially. Ultrasonic. Short-range, communication involves. The transmission. And reception of, sound. You. Topic. Electromagnetic. Induction. Electromagnetic. Induction only, allows short-range. Communication and. Power transmission, it. Has been used in biomedical, situations. Such as pacemakers as well as for short-range RFID. Tags. You. Topic. Services. Common. Examples of, wireless equipment. Include. Infrared. And ultrasonic remote. Control, devices. Professional. LMR, land, mobile radio an SMR, specialized. Mobile radio, typically. Used by business, industrial, and, public safety entities. Consumer. Two-way, radio, including FRS. Family, Radio Service. Gmrs. General. Mobile radio service and citizens, band. CB. Radios. The. Amateur, radio service. Ham radio. Consumer. And professional marine. VHF radios. Air. Band, and radio navigation, equipment used, by aviators. And air traffic control. Cellular. Telephones, and pagers, provide, connectivity for, portable, and mobile applications. Both personal, and business. Global. Positioning System. GPS allows. Drivers of cars and trucks captains. Of boats and ships and pilots, of aircraft to, ascertain, their location, anywhere, on earth. Cordless. Computer. Peripherals, the cordless mouse is a common, example wireless. Headphones, keyboards. And Printers can also be linked to a computer, via wireless, using, technology. Such as wireless, USB. Or bluetooth. Cordless. Telephone, sets these are limited range devices. Not to be confused with cell phones. Satellite. Television. Is broadcast. From satellites, in geostationary. Orbit, typical. Services, use Direct, broadcast satellite. To. Provide multiple television. Channels, to viewers. You. Topic. Electromagnetic. Spectrum. AM, and FM radios. And other electronic.
Devices Make, use of the electromagnetic. Spectrum. The. Frequencies. Of the radio spectrum that are available for, use for communication. Are treated as a public resource, and are regulated, by organizations. Such as the American Federal. Communications. Commission, off come, in the United Kingdom the International. ITU, are or the European, ETS, I their. Regulations. Determine, which frequency. Ranges can be used for what purpose, and by whom in the. Absence, of such control, or alternative, arrangements. Such as a privatized. Electromagnetic. Spectrum, chaos, might result if for example airlines, did not have specific frequencies. To work under, and an amateur, radio operator. Was interfering, with a pilots ability to land an aircraft. Wireless. Communication. Spans the spectrum from nine kilohertz, to 300, gigahertz. You. Topic. Applications. You. Topic. Mobile. Telephones. One, of the best known examples of, wireless technology. As the mobile phone also, known as a cellular, phone with, more than 6.6. Billion mobile cellular, subscriptions worldwide. As, of the end of 2010. These. Wireless, phones use radio, waves from, signal transmission. Towers to enable their users to make phone calls from many locations, worldwide. They. Can be used within range of the mobile telephone, site used to house the equipment, required to transmit, and receive the, radio signals, from these instruments. You. Topic. Data. Communications. Wireless. Data communications. Allows wireless, networking, between desktop. Computers, laptops. Tablet. Computers, cell, phones and, other related devices. The. Various, available, technologies. Differ in local availability, coverage. Range in performance, and in some circumstances. Users employ, multiple connection. Types and switch between them using connection, manager, software or, a mobile VPN. To handle the multiple connections. As a secure, single, virtual, network. Supporting. Technologies. Include. Wi-Fi. As, a wireless, local area network that enables portable, computing, devices to connect easily with other devices, peripheries. And the internet. Standardized. As I Triple, E. 802.11. A/b/g/n. AC. Acts. Wi-Fi. Has linked speeds similar, to older standards, of wired Ethernet. Wi-Fi. Has, become the de facto standard, for, access, in private, homes within, offices. And at public hotspots. Some. Businesses, charge customers a monthly, fee for service, while, others have begun offering it free in an effort to increase the sales of their goods cellular. Data service, offers coverage within, a range of 10 to 15 miles from the nearest cell, site. Speeds. Have increased as, technologies. Have evolved, from earlier technologies. Such as GSM. CDMA, and. GPRS. Through, 3G, to 4G networks. Such as, WCDMA. Edge or, CDMA. 2000. As of. 2018. The proposed, next, generation. As 5g, low-power, wide area, networks, l, pwan. Bridge, the gap between Wi-Fi. And cellular for, low bitrate Internet, of Things IOT. Applications. Mobile. Satellite, communications. May be used where other wireless, connections, are unavailable, such, as in largely rural, areas, or remote locations. Satellite. Communications. Are especially important. For transportation. Aviation. Maritime. And military, use wireless. Sensor, networks, are responsible. For sensing, noise interference. And activity. In data collection networks. This. Allows us to detect relevant, quantities monitor. And collect data formulate. Clear user displays, and to perform decision-making. Functions. Wireless, data communications. Are used to span a distance, beyond the capabilities. Of typical, cabling, in point-to-point. Communication. And point-to-multipoint, communication. To. Provide a backup, communications. Link in case of normal network, failure, to link portable, or temporary, workstations. To overcome, situations. Where normal, cabling, is difficult, or financially. Impractical or, to remotely connect, mobile users, or networks. Topic. Peripherals. Peripheral. Devices, in computing, can also be connected wirelessly as, part, of a Wi-Fi network or directly, via an optical, or radio frequency RF.
Peripheral. Interface. Originally. These units, used bulky, highly, local transceivers. To mediate between a computer, and a keyboard and mouse however, more, recent, generations. Have used smaller higher, performance. Devices. Radio. Frequency, interfaces. Such, as Bluetooth, or wireless, usb, provide, greater ranges, of efficient, use usually. Up to 10 feet but distance, physical, obstacles. Competing. Signals, and even, human bodies can alter grade the signal quality. Concerns. About the security, of wireless, keyboards, arose at the end of 2007. When it was revealed that Microsoft's. Implementation of. Encryption, in some of its 27. Megahertz, models, was highly, insecure. You. Topic. Energy. Transfer. Wireless. Energy transfer, as a process, whereby electrical. Energy, is transmitted, from a power source, to an electrical, load that does not have a built-in power source, without the use of interconnecting. Wires, there. Are two different, fundamental, methods for wireless energy transfer, energy, can. Be transferred, using either far-field methods, that involve beaming, power lasers. Radio, or microwave, transmissions. Are near-field using, electromagnetic, induction. Wireless. Energy transfer, may, be combined, with wireless, information. Transmission, in what is known as wireless powered, communication. You. Topic. Medical. Technologies. New, wireless technologies. Such, as mobile body, area, networks, and ban have the capability. To monitor blood pressure heart, rate oxygen. Level and body temperature. The. EM ban works by sending low powered, wireless signals, to receivers, that feed into nursing stations, or monitoring, sites. This. Technology. Helps with the intentional. And unintentional risk. Of infection, or disconnection, that arise from wired connections. You. Topic. Categories, of. Implementations. Devices. And standards. Equals. Equals, see also.
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