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)GSM (Global System for Mobile) is a communication standard for GSM cell phones very popular in the world. In fact, GSM is used by over 3 billion people across more than 212 countries and territories. What is so great about this standard is that it makes international roaming very common between mobile phone operators, making possible for them to use their phones in many countries around the world.
GSM is a cellular network that operates in four different frequency ranges. Most GSM networks use the 900 MHz or 1800 MHz bands. Canada and the United States use the 850 MHz and 1900 MHz bands because the 900 and 1800 MHz frequency bands were already allocated. There are also 400 and 450 MHz frequency bands in some countries that were previously used for first-generation systems.
The number one feature of GSM is the Subscriber Identity Module (SIM), commonly known as a SIM card. The SIM is a removable smart card containing the subscriber’s information and phone book. It enables the user to retain his or her information on any compatible handsets. The user can also change operators and keep the same handset simply by changing the SIM. Some operators will block this by allowing the phone to use only a single SIM, or only a SIM issued by them; this practice is known as SIM locking, and is illegal in some countries. You can also find dual SIM phones allowing you to have two active phone numbers in the same phone. It’s like having two GSM phones in one.
Many operators in Australia, North America and Europe lock the mobiles they sell. The reason for this is the price of the mobile phone which is typically subsidised with revenue from subscriptions, and operators don’t want to subsidise competitor's mobiles. There is a few ways you can unlock your phone, usually for a fee, or you can buy directly an unlocked GSM cell phone. In some countries such as Belgium, Costa Rica, India, Indonesia, Pakistan, and Malaysia, all phones are sold unlocked. There is a variety of unlocked phones available on the market. You can purchase a dual-band, tri-band or quad-band international cell phone at an affordable price. Often those will come with extra features like MP3/MP4 media player, PDA smartphone, camera, digital photo viewers, electronic book reader, etc. It is possible for you to select a handheld product with all the tools to satisfy your multimedia needs.
SH Multimedia Devices
GSM is a cellular network that operates in four different frequency ranges. Most GSM networks use the 900 MHz or 1800 MHz bands. Canada and the United States use the 850 MHz and 1900 MHz bands because the 900 and 1800 MHz frequency bands were already allocated. There are also 400 and 450 MHz frequency bands in some countries that were previously used for first-generation systems.
The number one feature of GSM is the Subscriber Identity Module (SIM), commonly known as a SIM card. The SIM is a removable smart card containing the subscriber’s information and phone book. It enables the user to retain his or her information on any compatible handsets. The user can also change operators and keep the same handset simply by changing the SIM. Some operators will block this by allowing the phone to use only a single SIM, or only a SIM issued by them; this practice is known as SIM locking, and is illegal in some countries. You can also find dual SIM phones allowing you to have two active phone numbers in the same phone. It’s like having two GSM phones in one.
Many operators in Australia, North America and Europe lock the mobiles they sell. The reason for this is the price of the mobile phone which is typically subsidised with revenue from subscriptions, and operators don’t want to subsidise competitor's mobiles. There is a few ways you can unlock your phone, usually for a fee, or you can buy directly an unlocked GSM cell phone. In some countries such as Belgium, Costa Rica, India, Indonesia, Pakistan, and Malaysia, all phones are sold unlocked. There is a variety of unlocked phones available on the market. You can purchase a dual-band, tri-band or quad-band international cell phone at an affordable price. Often those will come with extra features like MP3/MP4 media player, PDA smartphone, camera, digital photo viewers, electronic book reader, etc. It is possible for you to select a handheld product with all the tools to satisfy your multimedia needs.
SH Multimedia Devices
Guide created: 12/04/08 (updated 01/10/09)
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