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Phones CDMA and CDMA standard is all about
CDMA 2000 - CDMA2000 is an extension of the standard two-generation cdmaOne. A further development was to be cdmaOne IS-95C, and this designation is often used by manufacturers. The official update standard developed by Qualcomm and approved by the ITU (International Telecommunication Union, International Telecommunication Union), is cdma2000. The documents Lucent Technologies common designation of IS-2000. Finally, the International Telecommunication Union (ITU) has selected ten projects proposed five third-generation radio interfaces of IMT-2000 (International Mobile Telecommunications System - 2000 - International System for Mobile Communications - 2000), among them - IMT-MC (Multi Carrier), which represents a modification of the multi-frequency system cdma2000, which provides backward compatibility with standard equipment, cdmaOne (IS-95). Another of the five standards of IMT-2000 - IMT-DS (Direct Spread) - is based on W-CDMA project and was the foundation of the European system UMTS. At the beginning of 2003 from 127 million CDMA users almost 15 million have used technology to cdma2000. During the first seven months of 2002, in Asia and the Americas was launched CDMA2000 networks 11 and the total number of these networks was 18. This is - 99% of the market 3G, on the IMT-MC had 14.8 million subscribers on UMTS - 0,13 million. However, it is worth noting that the phase is implemented cdma2000 1X is still not a full-fledged 3G, since it does not quite live up to the mandatory two megabits. Therefore, it is often called 2.5G. Originally cdma2000 (IMT-MC) were divided into two phases - 1X and 3X. It applies to the first phase called IS-95C. A second later called 1X EV (evolution), dividing it into two phases - cdma2000 1X EV-DO (data only), and cdma2000 1X EV-DV (data & voice). And that standard is cdma2000 1X EV-DO is meant by 3G IMT-MC. Standard 1x EV-DO TIA was adopted in October 2000 and provides the following scheme of operation: The unit will search the network at the same time 1x and 1X EV, performs data transfer using the 1X EV, voices - with 1x. Standard 1X EV-DV is fully consistent with the requirements of 3G. Now for the CDMA-450. It should be noted that the family of cdma2000 standards do not require a separate frequency bands and in the course of their evolution from cdmaOne can be implemented in all the frequency bands used by cellular mobile communication systems (450, 700, 800, 900, 1700, 1800, 1900, 2100 MHz .)CDMA 450 - CDMA at 450 MHz.
Cell Phones Cell Phone cdma-CDMA - a mobile communication device that uses a combination of broadcast and traditional telephone switching for telephone service in the area (coverage), which consists of "hundreds" of surrounding base stations of cellular networks. Currently, mobile communication - the most common of all types of mobile communication, mobile phone so it is usually referred to as a cell phone, while mobile phones are in addition to cellular and cordless phones, satellite phones and devices trunking.
Phones cdma - phone standard CDMA.
1X EV-DO - a phase of development standarta mobile CDMA2000 1x. EV-DO - short for EVolution Data Only. In contrast, EV-DV (EVolution Data Voice) evolution has undergone only a data interface, a voice has remained completely identical with the CDMA2000 1x and CDMA One (IS-95a / b). The data transfer speed EV-DO reaches 2.4 megabits per second.
CDMA Ukraine-CDMA communications operator in Ukraine.
FDMA-(English Frequency Division Multiple Access - division multiple access channels by frequency) - how to use radio frequencies, where the same frequency band is only one person, different subscribers use different frequencies within the cell. Is the use of frequency division multiplexing (FDM) to radio communications. So while the initial request is not completed, the channel is closed to other communications. Full Duplex (Full-Duplex) FDMA transmission requires two channels, one for transmit and one for receiving. FDMA is used in the first generation (1G) analog communication, and this principle is implemented in a standard AMPS, N-AMPS, NMT, ETACS (American Standard).
WCDMA-Wideband Code Division Multiple Access - Wideband CDMA) - air interface technology is chosen by a majority of mobile operators to provide broadband wireless services to support 3G. The technology is optimized to provide high-speed multimedia services such as video, Internet access and video conferencing; provides access speeds up to 2 Mbit / s over short distances, and 384 kbit / s at large with full mobility. These values of data rates require wide bandwidth, so bandwidth is 5 MHz WCDMA. The technology can be added to the existing GSM networks and the PDC, WCDMA standard that makes the most promising in terms of network resources, and global interoperability.
SMS-Gateway-SMS Gateway - a system that allows subscribers of different standards (GSM, CDMA, DAMPS) to communicate seamlessly with each other through SMS-service.
TD-SCDMA - (English Time Division - Synchronous Code Division Multiple Access) - Chinese mobile standard of third generation networks. Designed to avoid the charges on the side for the use of proprietary technologies CDMA2000 and WCDMA.
CDMA cdma router-router
Cingular Wireless-Cingular Wireless, LLC, stationed in Atlanta, Georgia, United States - the largest mobile operator in the U.S. with more than 58.7 million subscribers. The company has the largest network of digital voice and data information in the United States. Cingular, in its current form, has been formed through mergers and acquisitions, and as a result of this - coupled with rapid technological changes in the field of wireless data transmission - Cingular operates networks ispolzuyushie different data transmission standards. The most widely used of them - the standard GSM. In addition to the networks of GSM, Cingular operates data networks GPRS, and networks based on EDGE (Enhanced Data rates for GSM Evolution).
D-AMPS-D-AMPS or Digital AMPS - digital mobile standard in the frequency range from 825 to 890 MHz. [Edit] Features capacity of cellular networks operating in DAMPS lower than in the fully digital systems (GSM, CDMA), but still significantly higher than in the analogue NMT-450 and AMPS. Channel bandwidth - 300 kHz Frequency Division Multiplexing FDMA as in AMPS. It is used in addition and division multiplexing vremennoe TDMA, in GSM and CDMA2000 1X EV-DO, only 3 timeslot (in GSM - 8 timeslots). In fact, a continuation of the American standard was DAMPS European standard GSM. The possibility of automatic roaming and SMS. The use of mobile devices in both digital and analog modes. If a subscriber with an analog telephone network into a digital AMPS falls - DAMPS, for him to stand out the analog channels. However, in this case, the advantages of digital communications, it is not available. The standard GSM loses the ability to freely change the old to the new phone models and porting old number to your new phone. In GSM this is the change of SIM-card in the DAMPS this have to do a special service center operator. But updated models in this sector is accelerating with each passing day, as the computer market. Recall that is issued a cell phone as a watch with voice dialing.
CDMA system-CDMA system.
CDMA technology-CDMA technology.
is 95 cdma-IS-95/cdmaOne (on the basis of which are designed, in particular, local TSPs), was designed and developed as a standard for mobile communications and is replete with mention of the word "mobile". So stop the "running buffalo" in terms of "fixed plane" is not easy. What to say about his descendants and other relatives such as broadband W-CDMA and cdma2000. In addition, it is CDMA technology enables the most high quality and transparent to the subscriber switching control when a subscriber moves between cells (so-called "soft" switching and soft hand-off), so that the companies valued operators and subscribers.
SMS-SMS (English Short Message Service - Short Message Service) - a system that allows you to send and receive text messages via cell phone. * With SMS you can maintain a kind of correspondence with something resembling a pager. * You can send a message to cut out / being out of service phone. As soon as your recipient will be released on bond, he will receive your message. * You can send a message to a subscriber who is currently engaged in conversation. * With Proof of Delivery Service SMS-messages can catch the moment of the subscriber's connection. * With the extended version of the SMS, are called the EMS, send / receive ring tones, icons, and much more. * You can subscribe to a mailing list to exchange rates, weather, etc. The SMS technology is supported by major cellular networks (GSM, NMT, D-AMPS, CDMA). Also, SMS-message to phones can be sent from the Internet and other networks (paging, fidonet, x.25, etc.), using special software, sms-universal form, as well as directly gateway mobile operators.
cdma news-cdma news.
Wi-Fi-(pronounced as [Wi-Fi], abbr. From the English. Wireless Fidelity - a standard for radio equipment for broadband designed to organize the local wireless networks, Wireless LAN. Installation of such networks is recommended where the deployment of cabling is impossible or economically inappropriate. Thanks to the handover, users can move between access points to the coverage Wi-Fi network without breaking the connection. A consortium of Wi-Fi Alliance standards-based IEEE 802.11. Wireless Internet Wireless internet access on the beach at the beach mobile devices (PDAs and laptops) equipped with Wi-Fi client receiving and transmitting devices can be connected to the LAN and access the Internet through the so-called access points or hotspots.
WAP-«Wireless Access Protocol" - a tool for accessing resources via the Internet only a cell phone without using a computer and / or modem. In essence this is a technical standard that describes the way in which information is transmitted from the Internet on mobile phone display. Theoretically, if the mobile phone screen could display a variety of information that the computer display, the WAP would be no different from the usual display of WEB-pages. But as the screen resolution screen mobile phone is small, the mapping WAP-sites differs poor graphics and animation, and the amount of information is reduced to the minimum necessary.
GPS-NAVSTAR GPS (English Navigation Satellite Time and Ranging, Global Positioning System - Measuring the distance and time from the satellite navigation, Global Positioning System) - a satellite navigation system, often referred to as GPS. Allows you to any place on Earth (including the polar regions), in almost any weather, and in outer space at a distance of up to 100 thousand kilometers from the Earth's surface, to determine the location and speed of objects. The system is designed, operated and carried at U.S. Department of Defense (born US Department of Defense).
CDMA modem-CDMA modem.
Verizon Wireless - the second largest cellular operator subscribers in the U.S.. As of April 2006, the size of the company's subscriber base stood at 56.7 million customers and coverage was most extensive in the U.S. cellular market. Recorded in New Jersey, the company is a joint venture of Verizon Communications and Vodafone Group, the distribution of shares in the equity of 55% and 45% respectively.
UMTS-UMTS («Universal Mobile Telecommunications Systems») - the third generation of mobile telephony in the medium term will replace the existing current GSM systems. UMTS provides two main components: radio network and carrier network. Radio network consists of mobile equipment and the base station, which switched between the transmission of data. The carrier network, in turn, connects the base stations with each other, and creates a connection to the ISDN network and the Internet. With a much greater bandwidth (5 MHz) than the GSM (200 kHz) and using the transmission method is CDMA (Code Division Multiple Access) is possible to transmit information of any type (multimedia applications, downloading from the Internet, video and audio) at high ( 2 Mbit / s) transfer rate. This makes UMTS up to 30 times faster than ISDN (64 kbit / s) and up to 200 times faster than the network of GSM (9,6 kbit / s). This allows you to transfer 2.1 video source in real time at full resolution and an acceptable quality. An interesting feature with respect to UMTS is not only in the fact that UMTS has a very high transmission capacity, but that he also supports multiple protocols such as TCP / IP, in combination with mobility.
EDGE-EDGE (English Enhanced Data rates for GSM Evolution) - Digital technology for mobile communications, which functions as an add-on 2G and 2.5G (GPRS) networks. This technology works in TDMA and GSM networks. EDGE - is empowering network GSM (to support EDGE in GSM networks require certain modifications and improvements). On the basis of EDGE can work: ECSD - faster access to the Internet via CSD, EHSCSD - faster access to the Internet via HSCSD, EGPRS - faster access to the Internet via GPRS. EDGE has been introduced to the world in 2003, initially in North America.
SIM-card-Subscriber Identification Module) - subscriber identification module, used in mobile communications. Sim card (extended) Sim Card (Up) SIM-cards are mainly used in the networks of GSM. Network 3G, next generation mobile networks, based on the principles of GSM, also has its own identification card, called a USIM. Subscriber cards are also sometimes used in networks such as CDMA / TDMA. The main function of SIM-card storage of identifying information on an account that allows you to easily and quickly change the mobile devices, without changing your account, simply rearranging your SIM card into another phone. While cell phones networks do not use SIM-card (AMPS, NAMPS, DAMPS, NMT-450), this information is stored in its internal memory and a change of telephone subscribers, while retaining the account can only be made by reprogramming the phone. What usually only associate cellular operator, the operator at the office for a fee. Also, SIM-card can store some additional information such as phone book subscriber lists of incoming / outgoing phone numbers, text SMS-messages, SIM-Info, ... SIM-card contains a memory chip that supports encryption. One SIM card can be assigned to multiple phone numbers stored in the HLR switch network. But none of the Russian mobile operators do not use this feature. SIM-card is installed in the SIM-holder cell phone, which in today's cell phones are usually located under the battery. Location of SIM-holder under the battery does not allow to install / remove SIM-card with the power on the phone. The first SIM cards were the size of a credit card, but with the minimization of cell phones, a new standard for smaller size.
| Generation | 1G | 2G | 2.5G | 3G | 3.5G | 4G |
|---|---|---|---|---|---|---|
| The beginning of development | 1970 | 1980 | 1985 | 1990 | <2000 | 2000 |
| Implementation | 1984 | 1991 | 1999 | 2002 | 2006-2007 | 2008-2010 |
| Services | analog standard, synchronous data transmission at speeds up to 9.6 kbit / s | Digital Standard, support for Short Message Service (SMS) | large capacity, packet data | an even greater capacity, speed up to 2 Mbit / s | increase in speed third-generation networks | high capacity, IP-oriented network, multimedia support, speeds of up to hundreds of megabits per second |
| Channel width | 1.9 kbit / s | 14.4 kbit / s | 384 kbit / s | 2 Mbit / s | 3-14 Mbit / s | 1 Gbit / s |
| Standards | AMPS, TACS, NMT | TDMA, CDMA, GSM, PDC | GPRS, EDGE, 1xRTT | WCDMA, CDMA2000, UMTS | HSDPA | a single standard |
| Network | PSTN | PSTN | PSTN, packet data | packet data | packet data | Internet |
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