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A dual-band phone operates at both the 900 MHz and 1800 MHz spectrum. Dual-band works in Europe, Africa, Asia, Australia, New Zealand and much of South America.
Tri-band - A tri-band phone operates on three frequency bands, 900 MHz, 1800 MHz and 1900 MHz, allowing you to use it in Europe, Africa, Asia, nearly all of North America, Australia and New Zealand.
Quad-band - A quad-band phone allows you to roam almost anywhere |
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globally. It covers the 850 Mhz, 900 MHz, 1800 MHz and 1900 MHz frequency ranges. Many countries in South America only have 850 MHz GSM service while both 1900 MHZ and 850 MHz GSM services are supported in the USA. 99% of all countries use the GSM standard. WE believe eventually GSM will be the only cell phone standard in the world. |
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What is GSM? |
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GSM (Global System for Mobile Communications) leads the world as the fastest growing, most reliable and advanced digital technology available in the marketplace today. GSM provides integrated voice mail, high-speed data, fax, paging and short message services capabilities. GSM customers enjoy secure communications, and GSM offers unparalleled call privacy and fraud prevention. As members of the GSM Global Network, GSM subscribers can use their phones at home, across town, across the |
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continent, or around the world (except for with country specific SIM cards). GSM operates on the multiple spectrum frequency bands used around the world - 1900MHZ, which is used in North America and 900MHz and 1800 MHz for other locations. Different mobile phone networks operate at different frequencies, which mean that if you wish to use your mobile phone outside your home country, you generally need a handset that supports multiple frequency bands. Make sure that the celluar phone you are interested in is compatible with the GSM band of the country you will use it in. GSM was first introduced in 1991. As of the end of 1997, GSM service was available in more than 100 countries and has become the de facto standard in Europe and Asia. |
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What is WCDMA? |
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Short for wide-band CDMA (Code-Division Multiple Access), a 3G technology that increases data transmission rates in GSM systems by using the CDMA air interface instead of TDMA. WCDMA is based on CDMA and is the technology used in UMTS. WCDMA was adopted as a standard by the ITU under the name "IMT-2000 direct spread". |
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What is CDMA? |
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Short for Code-Division Multiple Access, a digital cellular technology that uses spread-spectrum techniques. Unlike competing systems, such as GSM, that use TDMA, CDMA does not assign a specific frequency to each user. Instead, every channel uses the full available spectrum. Individual conversations are encoded with a pseudo-random digital sequence. CDMA consistently provides better capacity for voice and data communications than other commercial mobile technologies, allowing |
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more subscribers to connect at any given time, and it is the common platform on which 3G technologies are built.
CDMA is a military technology first used during World War II by English allies to foil German attempts at jamming transmissions. The allies decided to transmit over several frequencies, instead of one, making it difficult for the Germans to pick up the complete signal. Because Qualcomm created communications chips for CDMA technology, it was privy to the classified information. Once the information became public, Qualcomm claimed patents on the technology and became the first to commercialize it. |
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What is 3G? |
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3G is an ITU specification for the third generation (analog cellular was the first generation, digital PCS the second) of mobile communications technology. 3G promises increased bandwidth, up to 384 Kbps when a device is stationary or moving at pedestrian speed, 128 Kbps in a car, and 2 Mbps in fixed applications. 3G will work over wireless air interfaces such as GSM, TDMA, and CDMA. The new EDGE air interface has been developed specifically to meet the bandwidth needs of 3G. |
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What is a SIM card? |
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A SIM card or Subscriber Identity Module is a portable memory chip used in some models of cellular telephones. The SIM card makes it easy to switch to a new phone by simply sliding the SIM out of the old phone and into the new one. The SIM holds personal identity information, cell phone number, phone book, text messages and other data. It can be thought of as a mini hard disk that automatically activates the phone into which it is inserted.
A SIM card can come in very handy. For example, let's say your phone runs |
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out of battery power at a friend's house. Assuming you both have SIM-based phones, you can remove the SIM card from your phone and slide it into your friend's phone to make your call. Your carrier processes the call as if it were made from your phone, so it won't count against your friend's minutes.
If you upgrade your phone there's no hassle involved. The SIM card is all you need. Just slide it into the new phone and you're good to go. You can even keep multiple phones for different purposes. An inexpensive phone in the glove compartment, for example, for emergency use, one phone for work and another for home. Just slide your SIM card into whatever phone you wish to use.
High-end cell phones can be very attractive and somewhat pricey. If you invest in an expensive phone you might want to keep it awhile. Using a SIM card, it is even possible to switch carriers and continue to use the same phone. The new carrier will simply issue you their own SIM card. The phone must be unlocked, however, and operate on the new carrier's frequency or band.
A SIM card provides an even bigger advantage for international travelers -- simply take your phone with you and buy a local SIM card with minutes. For example, a traveler from the U.S. staying in the U.K. can purchase a SIM card across the pond. Now the phone can be used to call throughout England without paying international roaming charges from the carrier back home.
SIM cards are used with carriers that operate on the Global System for Mobile Communication (GSM) network. The competing network is Code Division Multiple Access (CDMA), a technology created by U.S. company Qualcomm. As of fall 2005, CDMA cell phones and CDMA carriers do not support SIM cards in most parts of the world, though this is changing. A CDMA SIM card called the R-UIM (Re-Useable Identification Module) was made available in China in 2002, and will eventually be available worldwide. Expectations for the future include a cell phone market that supports both SIM (GSM) and R-UIM (CDMA) cards by default. |
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What are Pre-Paid Phone Cards? |
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A pre-paid phone card is a card you purchase to make long distance phone calls. Many people use a pre-paid phone card because of the card's convenience - it can be used anywhere and, because you pay in advance, there is no bill. Pre-paid phone cards are popular among travelers, students, people who frequently call overseas, and those who haven't selected a preferred long distance telephone company. In addition, pre-paid phone cards are sold in convenient places, such as newsstands, post offices, and stores. |
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Recharge service is also called top up minutes. It is the basic service for SIM card. Whenever your SIM card is unable to make calls, it is mostly cause of the running out of minutes. The example can be seen at http://www.pandaphone.com/airtime_recharge.htm. |
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What is SMS? |
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Short for Systems Management Server, a set of tools from Microsoft that assists in managing PCs connected to a local-area network (LAN). SMS enables a network administrator to create an inventory of all the hardware and software on the network and to store it in an SMS database. Using this database, SMS can then perform software distribution and installation over the LAN. SMS also enables a network administrator to perform diagnostic tests on PCs attached to the LAN. SMS runs under Windows NT but can |
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manage PCs running DOS, all varieties of Windows, and OS/2, as well as Macintosh clients.
Short for Short Message Service Similar to paging, SMS is a service for sending short text messages to mobile phones. |
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What is EMS? |
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Also known as EMS (Expanded Memory Specification), expanded memory is a technique for utilizing more than 1MB of main memory in DOS -based computers. The limit of 1MB is built into the DOS operating system. The upper 384K is reserved for special purposes, leaving just 640K of conventional memory for programs.
There are several versions of EMS. The original versions, called EMS 3.0 and 3.2, enable programs to use an additional 8MB of memory, but for |
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data only. An improved version developed by AST, Quadram and Ashton-Tate is known as EEMS (Extended EMS). EEMS enables programs to use extra memory for code as well as for data. The most recent version of EMS (created in 1987) is known as EMS 4.0 or LIM 4.0, LIM being the initials of the three companies that developed the specification: Lotus, Intel, and Microsoft. EMS 4.0 raises the available amount of memory to 32MB.
Until the release of Microsoft Windows 3.0 in 1990, expanded memory was the preferred way to add memory to a PC. The alternative method, called extended memory, was less flexible and could be used only by special programs such as RAM disks. Windows 3.0 and all later versions of Windows, however, contain an extended memory manager that enables programs to use extended memory without interfering with one another. In addition, Windows can simulate expanded memory for those programs that need it (by using the EMM386.EXE driver).
Abbreviated as EMS, an application-level extension to SMS for cellular phones available on GSM, TDMA and CDMA networks. An EMS-enabled mobile phone can send and receive messages that have special text formatting (such as bold or italic), animations, pictures, icons, sound effects and special ring tones.
EMS messages that are sent to devices that do not support it will be displayed as SMS transmissions.
EMS, also referred to as Enhanced Messaging Service, is a cross-industry collaboration between Ericsson, Motorola, Siemens and Alcatel, among others.
Also see SMS and MMS. |
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What is MMS? |
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Short for Multimedia Message Service.
Abbreviated as MMS, Multimedia Message Service is a store-and-forward method of transmitting graphics, video clips, sound files and short text messages over wireless networks using the WAP protocol. Carriers deploy special servers, dubbed MMS Centers (MMSCs) to implement the offerings on their systems. MMS also supports e-mail addressing, so the device can send e-mails directly to an e-mail address. The most common use of MMS is for communication between mobile phones. |
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What is advanced Mobile Phone Service? |
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A standard system for analogue mobile communications originated in the United States but is also used in other countries, for example in Canada. AMPS operates in the 800 and 900 MHz frequency bands. |
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What is air time? |
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The time that is used for wireless transmission, for example making or receiving mobile calls, sending or receiving short messages, or using any service requiring a connection to the network. Sometimes air time is measured for charging purposes. |
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What is antenna? |
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A physical device for sending or receiving radio signals. Mobile devices can contain internal antennas or antennas that extend above the phone. If a mobile device includes an FM radio, the lead of the headset functions as the antenna of the radio. The headset needs to be connected when using the radio. |
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What is Bluetooth? |
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A technology that provides short-range radio links to allow mobile computers, mobile phones, digital cameras, and other portable devices to communicate with each other without cables. A Nokia mobile device with Bluetooth support allows the user to connect wirelessly to another compatible Bluetooth device within a short range. |
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What is cellular? |
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Relate to using cells for radio transmission. |
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What is code division multiple access? |
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A digital transmission technique in a base station assigns a unique code to each mobile device to distinguish that particular device from all others on the air. The signals are encoded using the code that the receiver also knows and uses to decode the received signal. CDMA is one of several spread spectrum techniques. |
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What is coverage area? |
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An area within a mobile device can have a connection to a network. |
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What is dead spot? |
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A geographic location within the coverage area of a wireless network where radio signals cannot be received. Dead spots are often caused by electrical interference or physical barriers such as hills, tunnels, and indoor parking garages. |
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What is EDGE? |
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A faster version of the GSM wireless service delivers data at higher rates. EDGE enables faster high speed circuit switched data (HSCSD) and general packet radio service (GPRS) connections. It enables the delivery of multimedia and other broadband applications to mobile phone and computer users. |
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What is GSM 1800 system? |
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A GSM mobile communication system operates in the 1800 MHz frequency band. |
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What is GSM 1900 system? |
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A GSM mobile communication system operates in the 1900 MHz frequency band. |
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What is GSM 900 system? |
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The original GSM mobile communication system operates in the 900 MHz frequency band. GSM 900 system is used in most European and Asian countries. |
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What is IMAP4? |
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A version of the Internet message access protocol (IMAP) that lets the user access and manipulate e-mail messages while the messages are still on the mail server. The user can then choose which messages to download to their device. |
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What is infrared port? |
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A port enables two compatible computers or a computer and another compatible device to use an infrared beam to communicate with each other. Line of sight is required, but no cable is needed. |
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What is integrated services digital network? |
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An integrated digital network in which a single wire or optical fibre is used to carry both voice and data. ISDN has a high data transfer rate (64 kilobits per second) compared to a standard landline (33.2 kilobits per second). |
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What is mobile wallet? |
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A feature in some wireless devices which lets the user securely store personal information, such as payment card details and user names. The user can retrieve the information from the wallet when needed, to use a mobile service that requires a user name and a password or to make an online purchase. The wallet is typically used via a browser. |
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What is PIN code? |
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An access code protects the SIM card against unauthorized use. A PIN code may be required by a service provider to make outgoing calls or obtain access to certain applications and data. |
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What is POP3? |
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A version of the post office protocol is used to store and retrieve e-mail or Internet mail messages. POP3 is used in conjunction with the simple mail transfer protocol (SMTP). |
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What is push to talk? |
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A one-way communication function in a mobile phone which lets one user at a time talk to another user or a selected user group. Push to talk is activated by pressing the push to talk key or equivalent on the phone. In a user group, the turns to speak are requested by pressing the push to talk key and granted on a first come, first served basis. |
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What is service provider? |
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A company t provides or hosts services or content either for end users or for other entities such as other service providers. A service provider provides, for example, mobile services for its customers. |
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What is TCP/IP? |
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It is the basic communication language or protocol of the Internet. It can also be used as a communications protocol in a private network.
What is universal Mobile Telecommunications System?
A European third generation mobile communication system is based on WCDMA technology and standardized by ETSI. Besides voice and data, UMTS enables audio and video delivery to wireless devices. |
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Recharge service is also called top up minutes. It is the basic service for SIM card. Whenever your SIM card is unable to make calls, it is mostly cause of the running out of minutes. The example can be seen at http://www.pandaphone.com/airtime_recharge.htm. |
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