What is GSM?
GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile), is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second-generation (2G) digital cellular networks used by mobile phones. As of 2014 it has become the default global standard for mobile communications - with over 90% market share, operating in over 219 countries and territories.[2]
2G networks developed as a replacement for first generation (1G) analog cellular networks, and 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 GPRS (General Packet Radio Services) and EDGE (Enhanced Data rates for GSM Evolution or EGPRS).
GSM carrier frequencies
GSM networks operate in a number of different carrier frequency ranges (separated into GSM frequency ranges for 2G and UMTS frequency bands for 3G), with most 2G GSM networks operating in the 900 MHz or 1800 MHz bands. Where these bands were already allocated, the 850 MHz and 1900 MHz bands were used instead (for example in Canada and the United States). In rare cases the 400 and 450 MHz frequency bands are assigned in some countries because they were previously used for first-generation systems.
Most 3G networks in Europe operate in the 2100 MHz frequency band. For more information on worldwide GSM frequency usage, see GSM frequency bands.
Regardless of the frequency selected by an operator, it is divided into timeslots for individual phones. This allows eight full-rate or sixteen half-rate speech channels per radio frequency. These eight radio timeslots (or burst periods) are grouped into a TDMA frame. Half-rate channels use alternate frames in the same timeslot. The channel data rate for all 8 channels is 270.833 kbit/s, and the frame duration is 4.615 ms.
The transmission power in the handset is limited to a maximum of 2 watts in GSM 850/900 and 1 watt in GSM 1800/1900.
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Source: Wikipedia
For more information about this subject, visit this link on wikipedia
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Hi All,
is there anyway to determine what GSM frequency band a WM5 phone is currently using?
I would like to know if my WM5 device is using a 900 or 1800 MHz GSM band. The device is quad-band capable and the network I am on is dual-band 900/1800. I can't find any GSM hash codes to report the information and I've had a quick look through extended TAPI but can't see anything.
Building on from that is there anyway to force a WM5 device to only use 900 or 1800? i.e. the mobile would only report itself to the network as being 900 or 1800 capable...but not both.
Thanks, rhd
Hi , my phone has WCDMA along with GSM (XPERIA X1) but can't read a regular CDMA simcard !
I asked the network service but didn't get much help .
So is WCDMA really CDMA ? or is it a name for UMTS ?
Hass_x1 said:
Hi , my phone has WCDMA along with GSM (XPERIA X1) but can't read a regular CDMA simcard !
I asked the network service but didn't get much help .
So is WCDMA really CDMA ? or is it a name for UMTS ?
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WCDMA is an alias for UMTS.
Swyped from my HTC Desire running LeeDrOiD 2.3d with Tapatalk.
BodenM said:
WCDMA is an alias for UMTS.
Swyped from my HTC Desire running LeeDrOiD 2.3d with Tapatalk.
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But whatever you call it, it still uses the technology named "Code division multiple access", right ?
And a device supporting what is called WCDMA/UMTS only (and NOT what is called CDMA), will not speak to CDMA only cell sites.
Get's confusing when names are used in different contexts.
WCDMA is just a technology used in many networks, but it is used synonymously for the UMTS family (3GPP) as it is one of the core technologies in that 3g network technology.
CDMA is also just a technology used in even more networks, but may be falsely used synonymously for CDMA2000 (3GPP2) which is the technical name for the 3g networks used in the US for example.
Here are some Wikipedia Articles that should shed some light into the whole terms:
3GPP: http://en.wikipedia.org/wiki/3GPP (That are the people behind UMTS)
3GPP2: http://en.wikipedia.org/wiki/3rd_Generation_Partnership_Project_2 (That are the people behind the concurrinng technology used in the U.S.)
CDMA: http://en.wikipedia.org/wiki/Code_division_multiple_access (A networking technology not only used in mobile systems, but also in GPS for example)
W-CDMA: http://en.wikipedia.org/wiki/W-CDMA_(UMTS) (1.: Air interface most commonly used in UMTS Networks based on CDMA 2.: WRONGLY used synonymously for UMTS)
CDMA2000: http://en.wikipedia.org/wiki/CDMA2000 (Has two meanings: 1.: Air interface "CDMA2000 1X" that is the concurring technology to wcdma but serves the same purpose 2.: Family Name of Network Protocols also known as US-3G ### Here the synonymous usage for Air interface and Protocol family is ok as they are really named the same ###)
UMTS: http://en.wikipedia.org/wiki/Universal_Mobile_Telecommunications_System (Family Name of Network Protocols that uses WCDMA as an Air Interface and is commonly found as the 3G Network in Europe and Asia)
The post-3g mobile networks will use a single technology as the 3GPP2 companies stopped development of their own 4G standard in favor of LTE (a post-3g and not really 4g standard) and LTE Advanced (which will fully comply with the 4G definition).
Where LTE (Advanced) is based on the UMTS technology by the 3GPP People.
LTE: http://en.wikipedia.org/wiki/3GPP_Long_Term_Evolution (Post-3g / Pre-4g network based on UMTS)
LTE Advanced: http://en.wikipedia.org/wiki/LTE_Advanced (The "real" 4G network)
4G: http://en.wikipedia.org/wiki/4G (4th generation wireless cellular standard that is currently in the make)
CDMA is just a theoretical type of air interface... how the physical layer and data link layer work. I wouldn't expect all CDMA to be created equal. Not sure how Verizon got to the point where it became synonymous with CDMA, because lots of carriers use the technology. Each implementation varies quite a bit in terms of spectrum allocation, time division and things like that.
I'm in australia and on Telstra (850Mhz and 2100Mhz).
The main network is 850Mhz but its congested as, and ironically the 'secondary' 2100 network seems to perform better in a lot of areas. However its only really good where the 850 has a problem, and vice versa. Hence I don't want to lock it to that network.
Is there a code I can enter (those *# codes) to do this? as opposed to manually selecting the 2100 network in settings. Or is that the same as long as I've enabled national roaming?!?
UMTS stands for Universal Mobile Telecommunication System. This system is used to handle high data traffic. It is a 3G networking standard which is used throughout much of the world as an upgrade to existing GSM mobile networks. UMTS makes use of WCDMA technology that shares much with CDMA networks used throughout the world, though it’s not compatible with them.Universal Mobile telecommunication system (UMTS) is one of the third generation (3G) mobile technologies, that uses WCDMA as the underlying standard and is standardized by the Third Generation Partnership Project (3GPP) and represents the European answer to International Telecommunication Union\’s (ITU) International Mobile Telecommunication 2000 necessities for 3G cellular radio systems.
UMTS supports transfer of data rate up to 1920 Kbit/s, but in a heavily loaded real-world system, typical users can expect performance of around 384 Kbit/s. But this is much greater than the 14.4Kbit/s of a single GSM error corrected data channel or multiple 14.4 Kbit/s channels in HSCSD, and offer the primary prospect of practical inexpensive access the World Wide Web on a mobile device and for the general use of MMS.
Thanks for this article, his commercial calling IS 3G, 3G+ for HSPA, for information.
Hello guys, so sry for my English, because i`m from Ukraine. I have trouble with GSM.. I can`t use this standart, only WCDMA\LTE.When I tap on the "Only GSM" phone don`t registered.. I think it`s error in the Service Menu..
WCDMA (Wide Band Code Division Multiple Access) or UMTS (Universal Mobile Telephone System) – this standard has been developed to accept higher rates up to 2 Mbps (to 2 Mbps (local area access) or 384 Kbps (wide area access)) allowing to surf the net, use the videophone, download video…WCDMA is a third-generation (3G) mobile wireless technology.
http://cellphones.about.com/od/cell_phone_glossary/g/wcdma.htm
To obtain higher speeds, HSDPA (high speed downlink packet access) was introduced in version 5 of the WCDMA (3GPP). HSDPA allows data rates up to 10 Mbps (and 20 Mbps for MIMO (Multiple Input Multiple Output)).
http://www.wisegeek.com/how-do-i-choose-the-best-hsdpa-phones.htm
GSM/WCDMA (WCDMA preferred) – The GSM phone can use both 2G and 3G data communication and when signal strength is low 3G is favored more.
GSM only – The GSM phone use only 2G data communication. When the 2G signal is too low you get nothing.
WCDMA only – The GSM phone use only 3G data communication. When the 3G signal is too low you get nothing.
* WCDMA is the standard that most GSM carriers moved to when upgrading to 3G. Parts of the WCDMA standard are based on GSM technology. WCDMA networks are designed to integrate with GSM networks at certain levels. Most WCDMA phones include GSM as well, for backward compatibility. So you can leave it as it is.
Joku1981 said:
WCDMA (Wide Band Code Division Multiple Access) or UMTS (Universal Mobile Telephone System) – this standard has been developed to accept higher rates up to 2 Mbps (to 2 Mbps (local area access) or 384 Kbps (wide area access)) allowing to surf the net, use the videophone, download video…WCDMA is a third-generation (3G) mobile wireless technology.
http://cellphones.about.com/od/cell_phone_glossary/g/wcdma.htm
To obtain higher speeds, HSDPA (high speed downlink packet access) was introduced in version 5 of the WCDMA (3GPP). HSDPA allows data rates up to 10 Mbps (and 20 Mbps for MIMO (Multiple Input Multiple Output)).
http://www.wisegeek.com/how-do-i-choose-the-best-hsdpa-phones.htm
GSM/WCDMA (WCDMA preferred) – The GSM phone can use both 2G and 3G data communication and when signal strength is low 3G is favored more.
GSM only – The GSM phone use only 2G data communication. When the 2G signal is too low you get nothing.
WCDMA only – The GSM phone use only 3G data communication. When the 3G signal is too low you get nothing.
* WCDMA is the standard that most GSM carriers moved to when upgrading to 3G. Parts of the WCDMA standard are based on GSM technology. WCDMA networks are designed to integrate with GSM networks at certain levels. Most WCDMA phones include GSM as well, for backward compatibility. So you can leave it as it is.
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I know it`s all.. I can`t connect to 2G