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Wireless
Wireless communication (or just wireless, when the context allows) is the transfer of information (''telecommunication'') between two or more points without the use of an electrical conductor, optical fiber or other continuous guided transmission medium, medium for the transfer. The most common wireless technologies use radio waves. With radio waves, intended distances can be short, such as a few meters for Bluetooth, or as far as millions of kilometers for NASA Deep Space Network, deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, Mobile phone, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio ''wireless technology'' include Global Positioning System, GPS units, garage door openers, wireless Mouse (computing), computer mouse, Keyboard (computing), keyboards and Headset (audio), headsets, headphones, radio receivers, satelli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wi-Fi
Wi-Fi () is a family of wireless network protocols based on the IEEE 802.11 family of standards, which are commonly used for Wireless LAN, local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio waves. These are the most widely used computer networks, used globally in small office/home office, home and small office networks to link devices and to provide Internet access with wireless routers and wireless access points in public places such as coffee shops, restaurants, hotels, libraries, and airports. ''Wi-Fi'' is a trademark of the Wi-Fi Alliance, which restricts the use of the term "''Wi-Fi Certified''" to products that successfully complete Interoperability Solutions for European Public Administrations, interoperability certification testing. Non-compliant hardware is simply referred to as WLAN, and it may or may not work with "''Wi-Fi Certified''" devices. the Wi-Fi Alliance consisted of more than 800 companies from ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless Network
A wireless network is a computer network that uses wireless data connections between network nodes. Wireless networking allows homes, telecommunications networks, and business installations to avoid the costly process of introducing cables into a building, or as a connection between various equipment locations. Admin telecommunications networks are generally implemented and administered using radio communication. This implementation takes place at the physical level (layer) of the OSI model network structure. Examples of wireless networks include cell phone networks, WLAN, wireless local area networks (WLANs), wireless sensor networks, satellite communication networks, and terrestrial microwave networks. History Wireless networks The first professional wireless network was developed under the brand ALOHAnet in 1969 at the University of Hawaii and became operational in June 1971. The first commercial wireless network was the WaveLAN product family, developed by NCR Corpor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bluetooth
Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limited to 2.5 milliwatts, giving it a very short range of up to . It employs Ultra high frequency, UHF radio waves in the ISM bands, from 2.402GHz to 2.48GHz. It is mainly used as an alternative to wired connections to exchange files between nearby portable devices and connect cell phones and music players with wireless headphones, wireless speakers, HIFI systems, car audio and wireless transmission between TVs and soundbars. Bluetooth is managed by the Bluetooth Special Interest Group (SIG), which has more than 35,000 member companies in the areas of telecommunication, computing, networking, and consumer electronics. The Institute of Electrical and Electronics Engineers, IEEE standardized Bluetooth as IEEE 802.15.1 but no longer maintains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless Telegraphy
Wireless telegraphy or radiotelegraphy is the transmission of text messages by radio waves, analogous to electrical telegraphy using electrical cable, cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for transmitting telegraph signals without wires. In radiotelegraphy, information is transmitted by pulses of radio waves of two different lengths called "dots" and "dashes", which spell out text messages, usually in Morse code. In a manual system, the sending operator taps on a switch called a telegraph key which turns the transmitter on and off, producing the pulses of radio waves. At the radio receiver, receiver the pulses are audible in the receiver's speaker as beeps, which are translated back to text by an operator who knows Morse code. Radiotelegraphy was the first means of radio communication. The first practical radio transmitters and radio receiver, receivers invented in 1894–1895 by Guglielmo Marconi used radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile Broadband
Mobile broadband is the marketing term for Wireless broadband, wireless Internet access via mobile network, mobile (cell) networks. Access to the network can be made through a portable modem, wireless modem, or a Tablet computer, tablet/smartphone (possibly Tethering, tethered) or other mobile device. The first wireless Internet access became available in 1991 as part of the second generation (2G) of mobile phone technology. Higher speeds became available in 2001 and 2006 as part of the third (3G) and fourth (4G) generations. In 2011, 90% of the world's population lived in areas with 2G coverage, while 45% lived in areas with 2G and 3G coverage."The World in 2011: ITC Facts and Figures" International Telecommunication Union (ITU), Geneva, 2011 Mobile broadband uses the spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headphone
Headphones are a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an audio source privately, in contrast to a loudspeaker, which emits sound into the open air for anyone nearby to hear. Headphones are also known as earphones or, colloquially, cans. Circumaural (around the ear) and supra-aural (over the ear) headphones use a band over the top of the head to hold the drivers in place. Another type, known as earbuds or earpieces, consists of individual units that plug into the user's ear canal; within that category have been developed cordless air buds using wireless technology. A third type are bone conduction headphones, which typically wrap around the back of the head and rest in front of the ear canal, leaving the ear canal open. In the context of telecommunication, a headset is a combination of a head ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headset (audio)
A headset is a combination of headphone and microphone. Headsets connect over a telephone or to a computer, allowing the user to speak and listen while keeping both hands free. They are commonly used in customer service and technical support centers, where employees can converse with customers while typing information into a computer. They are also common among computer gamers and let them talk with each other and hear others while using their keyboards and mice to play the game. Types Telephone headsets generally use loudspeakers with a narrower frequency range than those also used for entertainment. Stereo computer headsets, on the other hand, use 32-ohm speakers with a broader frequency range. Mono and stereo Headsets are available in single-earpiece and double-earpiece designs. Double-earpiece headsets may support stereo sound or use the same monaural audio channel for both ears. Single-earpiece headsets free up one ear, allowing better awareness of surroundings. Teleph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications Industry
The telecommunications industry within the sector of information and communication technology comprises all telecommunication/ telephone companies and Internet service providers, and plays a crucial role in the evolution of mobile communications and the information society. Telephone calls continue to be the industry's largest revenue generator, but due to advances in network technology, telecom today is less about voice and increasingly about text ( messaging, email) and images (e.g. video streaming). High-speed Internet access for computer-based data applications such as broadband information services and interactive entertainment is pervasive. Digital subscriber line (DSL) is the main broadband telecom technology. The fastest growth comes from (value-added) services delivered over mobile networks. Insight Research projected that telecommunications services revenue worldwide would grow from $2.2 trillion in 2015 to $2.4 trillion in 2019. Market segmentation Of all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keyboard (computing)
A computer keyboard is a built-in or peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or Push-button, keys to act as Mechanical keyboard, mechanical levers or Electronic switching system, electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input device, input method for computers since the 1970s, supplemented by the computer mouse since the 1980s, and the touchscreen since the 2000s. Keyboard keys (buttons) typically have a set of characters Engraving, engraved or Printing, printed on them, and each press of a key typically corresponds to a single written symbol. However, producing some symbols may require pressing and holding several keys simultaneously or in sequence. While most keys produce character (computing), characters (Letter (alphabet), letters, Numerical digit, numbers or symbols), other keys (such as the escape key) can prompt the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Receiver
In radio communications, a radio receiver, also known as a receiver, a wireless, or simply a radio, is an electronic device that receives radio waves and converts the information carried by them to a usable form. It is used with an antenna. The antenna intercepts radio waves (electromagnetic waves of radio frequency) and converts them to tiny alternating currents which are applied to the receiver, and the receiver extracts the desired information. The receiver uses electronic filters to separate the desired radio frequency signal from all the other signals picked up by the antenna, an electronic amplifier to increase the power of the signal for further processing, and finally recovers the desired information through demodulation. Radio receivers are essential components of all systems based on radio technology. The information produced by the receiver may be in the form of sound, video (television), or digital data. A radio receiver may be a separate piece of electronic equ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photophone
The photophone is a telecommunications device that allows transmission of speech on a beam of light. It was invented jointly by Alexander Graham Bell and his assistant Charles Sumner Tainter on February 19, 1880, at Bell's laboratory at 1325 L Street in Washington, D.C. Both were later to become full associates in the Volta Laboratory Association, created and financed by Bell. On June 3, 1880, Bell's assistant transmitted a wireless voice telephone message from the roof of the Franklin School to the window of Bell's laboratory, some 213 meters (about 700 ft.) away.Carson 2007, pg. 76–78Mims 1982, p. 11. Bell believed the photophone was his most important invention. Of the 18 patents granted in Bell's name alone, and the 12 he shared with his collaborators, four were for the photophone, which Bell referred to as his "greatest achievement", telling a reporter shortly before his death that the photophone was "the greatest invention haveever made, greater than the tele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile Phone
A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This radio frequency link connects to the switching systems of a mobile phone operator, providing access to the public switched telephone network (PSTN). Modern mobile telephony relies on a cellular network architecture, which is why mobile phones are often referred to as 'cell phones' in North America. Beyond traditional voice communication, digital mobile phones have evolved to support a wide range of additional services. These include text messaging, multimedia messaging, email, and internet access (via LTE, 5G NR or Wi-Fi), as well as short-range wireless technologies like Bluetooth, infrared, and ultra-wideband (UWB). Mobile phones also support a variety of multimedia capabilities, such as digital photography, video recordin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
