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W-CDMA
The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunication Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code-division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators. UMTS specifies a complete network system, which includes the radio access network (UMTS Terrestrial Radio Access Network, or UTRAN), the core network (Mobile Application Part, or MAP) and the authentication of users via SIM (subscriber identity module) cards. The technology described in UMTS is sometimes also referred to as Freedom of Mobile Multimedia Access (FOMA) or 3GSM. Unlike EDGE (IMT Single-Carrier, based on GSM) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
W-CDMA
The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunication Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code-division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators. UMTS specifies a complete network system, which includes the radio access network (UMTS Terrestrial Radio Access Network, or UTRAN), the core network (Mobile Application Part, or MAP) and the authentication of users via SIM (subscriber identity module) cards. The technology described in UMTS is sometimes also referred to as Freedom of Mobile Multimedia Access (FOMA) or 3GSM. Unlike EDGE (IMT Single-Carrier, based on GSM) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UMTS
The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunication Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code-division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators. UMTS specifies a complete network system, which includes the radio access network (UMTS Terrestrial Radio Access Network, or UTRAN), the core network (Mobile Application Part, or MAP) and the authentication of users via SIM (subscriber identity module) cards. The technology described in UMTS is sometimes also referred to as Freedom of Mobile Multimedia Access (FOMA) or 3GSM. Unlike EDGE (IMT Single-Carrier, based on GSM) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UMTS Structures
The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunication Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code-division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators. UMTS specifies a complete network system, which includes the radio access network (UMTS Terrestrial Radio Access Network, or UTRAN), the core network (Mobile Application Part, or MAP) and the authentication of users via SIM (subscriber identity module) cards. The technology described in UMTS is sometimes also referred to as Freedom of Mobile Multimedia Access (FOMA) or 3GSM. Unlike EDGE (IMT Single-Carrier, based on GSM) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Code-division Multiple Access
Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communication channel. This allows several users to share a band of frequencies (see bandwidth). To permit this without undue interference between the users, CDMA employs spread spectrum technology and a special coding scheme (where each transmitter is assigned a code). CDMA optimizes the use of available bandwidth as it transmits over the entire frequency range and does not limit the user's frequency range. It is used as the access method in many mobile phone standards. IS-95, also called "cdmaOne", and its 3G evolution CDMA2000, are often simply referred to as "CDMA", but UMTS, the 3G standard used by GSM carriers, also uses "wideband CDMA", or W-CDMA, as well as TD-CDMA and TD-SCDMA, as its radio technologies. It can be also used as a channel or m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freedom Of Mobile Multimedia Access
Freedom of Mobile Multimedia Access (FOMA) is the brand name of the W-CDMA-based 3G telecommunications services being offered by the Japanese telecommunications service provider NTT DoCoMo. It is an implementation of the Universal Mobile Telecommunications System (UMTS) and was the world's first 3G mobile data service to commence commercial operations. NTT DoCoMo also offers HSPA services branded FOMA High-Speed (FOMAハイスピード), which offers downlink speeds up to 7.2 Mbit/s and uplink speeds up to 5.7 Mbit/s. History NTT DoCoMo developed the W-CDMA air interface, which is a form of DS-CDMA (Direct Sequence CDMA), in the late 1990s. It was later accepted by the ITU as one of several air interfaces for the IMT-2000telecom initiative and by the ETSI as one of three air interfaces for the UMTS cellular network standard. NTT DoCoMo originally planned to launch the world's first 3G services, initially branded Frontier of Mobile Multimedia Access (FOMA), in May 2001. Howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3GPP Long Term Evolution
In telecommunications, long-term evolution (LTE) is a standard for wireless broadband communication for mobile devices and data terminals, based on the GSM/EDGE and UMTS/HSPA standards. It improves on those standards' capacity and speed by using a different radio interface and core network improvements. LTE is the upgrade path for carriers with both GSM/UMTS networks and CDMA2000 networks. Because LTE frequencies and bands differ from country to country, only multi-band phones can use LTE in all countries where it is supported. The standard is developed by the 3GPP (3rd Generation Partnership Project) and is specified in its Release 8 document series, with minor enhancements described in Release 9. LTE is also called 3.95G and has been marketed as "4G LTE" and "Advanced 4G"; but it does not meet the technical criteria of a 4G wireless service, as specified in the 3GPP Release 8 and 9 document series for LTE Advanced. The requirements were set forth by the ITU-R organisation ... [...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] |
IMT-2000
IMT-2000 (International Mobile Telecommunications-2000) is the global standard for third generation ( 3G) wireless communications as defined by the International Telecommunication Union. In 1999 ITU approved five radio interfaces for IMT-2000 as a part of the ITU-R M.1457 Recommendation. The five standards are: * ''IMT-2000 CDMA Direct Spread'' ** also known as W-CDMA, used in UMTS, the successor to GSM * ''IMT-2000 CDMA Multi-Carrier'' ** also known as CDMA2000, the successor to 2G CDMA (IS-95) * ''IMT-2000 CDMA TDD'' ** also known as TD-SCDMA * ''IMT-2000 TDMA Single Carrier'' ** also known as EDGE, an intermediate 2.5G technology * ''IMT-2000 FDMA/TDMA'' ** also known as DECT Digital enhanced cordless telecommunications (Digital European cordless telecommunications), usually known by the acronym DECT, is a standard primarily used for creating cordless telephone systems. It originated in Europe, where it is the common ... To meet the IMT-2000 standards, a system must provi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global System For Mobile Communications
The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation ( 2G) digital cellular networks used by mobile devices such as mobile phones and tablets. GSM is also a trade mark owned by the GSM Association. GSM may also refer to the Full Rate voice codec. It was first implemented in Finland in December 1991. By the mid-2010s, it became a global standard for mobile communications achieving over 90% market share, and operating in over 193 countries and territories. 2G networks developed as a replacement for first generation ( 1G) analog cellular networks. The GSM standard originally described a digital, circuit-switched network optimized for full duplex voice telephony. This expanded over time to include data communications, first by circuit-switched transport, then by packet data transport via General Packet Radio Service (GPRS), and Enhanced Data Rates for G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subscriber Identity Module
A typical SIM card (mini-SIM with micro-SIM cutout) A GSM mobile phone file:Simkarte NFC SecureElement.jpg, T-Mobile nano-SIM card with NFC capabilities in the SIM tray of an iPhone 6s file:Tf sim both sides.png, A TracFone Wireless SIM card has no distinctive carrier markings and is only marked as a "SIM card" A SIM card (full form Subscriber Identity Module or Subscriber Identification Module) is an integrated circuit (IC) intended to securely store the international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers). Technically the actual physical card is known as a universal integrated circuit card (UICC); this smart card is usually made of PVC with embedded contacts and semiconductors, with the SIM as its primary component. In practise the term "SIM card" refers to the entire unit and not simply the IC. A SIM contains a unique serial number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-Speed Uplink Packet Access
High Speed Packet Access (HSPA) is an amalgamation of two mobile protocols—High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA)—that extends and improves the performance of existing 3G mobile telecommunication networks using the WCDMA protocols. A further-improved 3GPP standard called Evolved High Speed Packet Access (also known as HSPA+) was released late in 2008, with subsequent worldwide adoption beginning in 2010. The newer standard allows bit rates to reach as high as 337 Mbit/s in the downlink and 34 Mbit/s in the uplink; however, these speeds are rarely achieved in practice. Overview The first HSPA specifications supported increased peak data rates of up to 14 Mbit/s in the downlink and 5.76 Mbit/s in the uplink. They also reduced latency and provided up to five times more system capacity in the downlink and up to twice as much system capacity in the uplink compared with original WCDMA protocol. High Speed Down ... [...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] |
