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WiGig Display Extension
WiGig, alternatively known as 60 GHz Wi-Fi, refers to a set of 60 GHz wireless network protocols. It includes the current IEEE 802.11ad standard and also the IEEE 802.11ay standard. The WiGig specification allows devices to communicate without wires at multi-gigabit speeds. It enables high performance wireless data, display and audio applications that supplement the capabilities of previous wireless LAN devices. WiGig tri-band-enabled devices, which operate in the 2.4, 5 and 60 GHz bands, deliver data transfer rates up to 7 Gbit/s (for 11ad), about as fast as an 8-band 802.11ac transmission, and more than eleven times as fast than the highest 802.11n rate, while maintaining compatibility with existing Wi-Fi devices. The 60 GHz millimeter wave signal cannot typically penetrate walls but can propagate by reflection from walls, ceilings, floors and objects using beamforming built into the WiGig system. When roaming away from the main room, the protocol can switch to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
V Band
The V band ("vee-band") is a standard designation by the Institute of Electrical and Electronics Engineers (IEEE) for a band of frequencies in the microwave portion of the electromagnetic spectrum ranging from 40 to 75 gigahertz (GHz). The V band is not heavily used, except for millimeter wave radar research and other kinds of scientific research. It should not be confused with the 600–1000 MHz range of Band V (Band Five) of the UHF frequency range. The V band is also used for high capacity terrestrial millimeter wave communications systems. In the United States, the Federal Communications Commission has allocated the frequency band from 57 to 71 GHz for unlicensed wireless systems. These systems are primarily used for high capacity, short distance (less than 1 mile or 1.6 km) communications. In addition, frequencies at 70, 80, and 90 GHz have been allocated as "lightly licensed" bands for multi-gigabit wireless communications. All communications l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DSSS
In telecommunications, direct-sequence spread spectrum (DSSS) is a spread-spectrum modulation technique primarily used to reduce overall signal interference. The direct-sequence modulation makes the transmitted signal wider in bandwidth than the information bandwidth. After the despreading or removal of the direct-sequence modulation in the receiver, the information bandwidth is restored, while the unintentional and intentional interference is substantially reduced. The first known scheme for this technique was introduced by a Swiss inventor, Gustav Guanella. With DSSS, the message bits are modulated by a pseudorandom bit sequence known as a spreading sequence. Each spreading-sequence bit, which is known as a chip, has a much shorter duration (larger bandwidth) than the original message bits. The modulation of the message bits scrambles and spreads the pieces of data, and thereby results in a bandwidth size nearly identical to that of the spreading sequence. The smaller the ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miracast
Miracast (also called screen mirroring and wireless display among other names on consumer devices) is a standard for wireless connections from sending devices (such as laptops, tablets, or smartphones) to display receivers (such as TVs, monitors, or projectors), introduced in 2012 by the Wi-Fi Alliance. It can roughly be described as "HDMI over Wi-Fi", replacing the cable from the device to the display.On Wifi-Display, Democratic Republics and Miracles Patrick Herrmann, on the development of Miraclecast, 2014-02-17. The launched the Miracast certification program at the end of 2012. Devices that are Miracast- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WiDi
Wireless Display (WiDi) is technology developed by Intel that enables users to stream music, movies, photos, videos and apps without wires from a compatible computer to a compatible HDTV or through the use of an adapter with other HDTVs or monitors. Intel WiDi supports HD 1080p video quality, 5.1 surround sound, and low latency for interacting with applications sent to the TV from a PC. Using the Intel WiDi Widget, users can perform different functions simultaneously on their PC and TV such as checking email on the PC while streaming a movie to the TV from the same device. WiDi was discontinued in 2015 in favour of Miracast, a standard developed by the Wi-Fi Alliance and natively supported by Windows 8.1 and later. In Microsoft's Windows 10 operating system, the built-in Wireless Display is called Project, which can be used to mirror the device's display to a TV if it supports Miracast. Version history *2010 - WiDi 1.0 - Supports 720p *2011 - WiDi 2.0 - Supports 1080p *2012 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless HDMI
Wireless HDMI is a colloquial term for wireless high-definition audio and video signals connectivity on consumer electronics products. Currently, most HD wireless transmission technologies use unlicensed 5 GHz, 60 GHz or 190 GHz radio frequencies and include: * various proprietary protocols for wireless transmission (LG "Wireless 1080p", Philips "Wireless HDTV Link", Sony "Bravia Wireless Link", Asus "Wireless Display Connectivity", etc.); * there are several technologies attempting to become the industry standards like WirelessHD, Wireless Home Digital Interface and the WiGig; * proprietary video compression schemes that work over 802.11n and similar wireless interfaces; * Asus WAVI (Wireless Audio Video Interaction) wireless HDMI use 4 x 5 MIMO-channels with Two-Way Wireless USB Control. Wireless HDTV (aka WiDi) availability is currently an ongoing development. In 2010, Toshiba began marketing the first WiDi device. See also * WirelessHD * Wireless Home Digital Interface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultra-wideband
Ultra-wideband (UWB, ultra wideband, ultra-wide band and ultraband) is a radio technology that can use a very low energy level for short-range, high-bandwidth communications over a large portion of the radio spectrum. UWB has traditional applications in non-cooperative radar imaging. Most recent applications target sensor data collection, precise locating, and tracking. UWB support started to appear in high-end smartphones 2019. Characteristics Ultra-wideband is a technology for transmitting information across a wide bandwidth (>500 MHz). This allows for the transmission of a large amount of signal energy without interfering with conventional narrowband and carrier wave transmission in the same frequency band. Regulatory limits in many countries allow for this efficient use of radio bandwidth, and enable high-data-rate personal area network (PAN) wireless connectivity, longer-range low-data-rate applications, and the transparent co-existence of radar and imaging systems with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless USB
Wireless USB (Universal Serial Bus) was a short-range, high-bandwidth wireless radio communication protocol created by the Wireless USB Promoter Group which intended to increase the availability of general USB-based technologies. It was unrelated to Wi-Fi, and different from the Cypress WirelessUSB offerings. It was maintained by the WiMedia Alliance which ceased operations in 2009. Wireless USB is sometimes abbreviated as "WUSB", although the USB Implementers Forum discouraged this practice and instead prefers to call the technology Certified Wireless USB to distinguish it from the competing UWB standard. Wireless USB was based on the (now defunct) WiMedia Alliance's Ultra-WideBand (UWB) common radio platform, which is capable of sending 480 Mbit/s at distances up to and 110 Mbit/s at up to . It was designed to operate in the 3.1 to 10.6 GHz frequency range, although local regulatory policies may restrict the legal operating range in some countries. The standard is now obsole ... [...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 UHF radio waves in the ISM bands, from 2.402GHz to 2.48GHz. It is mainly used as an alternative to wire connections, to exchange files between nearby portable devices and connect cell phones and music players with wireless headphones. 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 IEEE standardized Bluetooth as IEEE 802.15.1, but no longer maintains the standard. The Bluetooth SIG oversees development of the specification, manages the qualification program, and protects the trademarks. A manufacturer must meet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gi-Fi
Gi-Fi or gigabit wireless refers to a wireless communication at a data rate of more than one billion bits (gigabit) per second. By 2004 some trade press used the term "Gi-Fi" to refer to faster versions of the IEEE 802.11 standards marketed under the trademark Wi-Fi. In 2008 researchers at the University of Melbourne demonstrated a transceiver integrated on a single integrated circuit (chip) that operated at 60 GHz on the CMOS process. It will allow wireless transfer of audio and video data at up to 5 gigabits per second, ten times the current maximum wireless transfer rate, at one-tenth the cost. Researchers chose the 57–64 GHz unlicensed frequency band since the millimetre-wave range of the spectrum allowed high component on-chip integration as well as the integration of very small high gain arrays. The available 7 GHz of spectrum results in very high data rates, up to 5 gigabits per second to users within an indoor environment, usually within a range of 10 metre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SQPSK
Phase-shift keying (PSK) is a digital modulation process which conveys data by changing (modulating) the phase of a constant frequency reference signal (the carrier wave). The modulation is accomplished by varying the sine and cosine inputs at a precise time. It is widely used for wireless LANs, RFID and Bluetooth communication. Any digital modulation scheme uses a finite number of distinct signals to represent digital data. PSK uses a finite number of phases, each assigned a unique pattern of binary digits. Usually, each phase encodes an equal number of bits. Each pattern of bits forms the symbol that is represented by the particular phase. The demodulator, which is designed specifically for the symbol-set used by the modulator, determines the phase of the received signal and maps it back to the symbol it represents, thus recovering the original data. This requires the receiver to be able to compare the phase of the received signal to a reference signal such a system is terme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Error Vector Magnitude
The error vector magnitude or EVM (sometimes also called relative constellation error or RCE) is a measure used to quantify the performance of a digital radio transmitter or receiver. A signal sent by an ideal transmitter or received by a receiver would have all constellation points precisely at the ideal locations, however various imperfections in the implementation (such as carrier leakage, low image rejection ratio, phase noise etc.) cause the actual constellation points to deviate from the ideal locations. Informally, EVM is a measure of how far the points are from the ideal locations. Noise, distortion, spurious signals, and phase noise all degrade EVM, and therefore EVM provides a comprehensive measure of the quality of the radio receiver or transmitter for use in digital communications. Transmitter EVM can be measured by specialized equipment, which demodulates the received signal in a similar way to how a real radio demodulator does it. One of the stages in a typical ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OFDM
In telecommunications, orthogonal frequency-division multiplexing (OFDM) is a type of digital transmission and a method of encoding digital data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, used in applications such as digital television and audio broadcasting, DSL internet access, wireless networks, power line networks, and 4G/ 5G mobile communications. OFDM is a frequency-division multiplexing (FDM) scheme that was introduced by Robert W. Chang of Bell Labs in 1966. In OFDM, multiple closely spaced orthogonal subcarrier signals with overlapping spectra are transmitted to carry data in parallel.webe.org - 2GHz BAS Relocation Tech-Fair, COFDM Technology Basics 2007-03-02 Demodula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
