Difference between GSM,CDMA & TDMA technologies of Cell Phones.
GSM:
GSM, which stands for Global System for Mobile communications, reigns as the world’s most widely used cell phone technology. Cell phones use a cell phone service carrier’s GSM network by searching for cell phone towers in the nearby area. The origins of GSM can be traced back to 1982 when the Groupe Special Mobile (GSM) was created by the European Conference of Postal and Telecommunications Administrations (CEPT) for the purpose of designing a pan-European mobile technology. It is approximated that 80 percent of the world uses GSM technology when placing wireless calls, according to the GSM Association (GSMA), which represents the interests of the worldwide mobile communications industry. This amounts to nearly 3 billion global people. GSM also has the advantage of using SIM (Subscriber Identity Module) cards in the U.S. The SIM card, which acts as your digital identity, is tied to your cell phone service carrier’s network rather than to the handset itself. This allows for easy exchange from one phone to another without new cell phone service activation.
CDMA:
CDMA, or Code Division Multiple Access, is a competing cell phone service technology to GSM, which is the world’s most widely used cell phone standard. CDMA uses a “spread-spectrum” technique whereby electromagnetic energy is spread to allow for a signal with a wider bandwidth. This allows multiple people on multiple cell phones to be “multiplexed” over the same channel to share a bandwidth of frequencies. With CDMA technology, data and voice packets are separated using codes and then transmitted using a wide frequency range. Since more space is often allocated for data with CDMA, this standard became attractive for 3G high-speed mobile Internet use. The CDMA standard was originally designed by Qualcomm in the U.S. and is primarily used in the U.S. and portions of Asia. While CDMA and GSM compete head on in terms of higher bandwidth speed (i.e. for surfing the mobile Web), GSM has more complete global coverage due to roaming and international roaming contracts. GSM technology tends to cover rural areas in the U.S. more completely than CDMA. Over time, CDMA won out over less advanced TDMA technology, which was incorporated into more advanced GSM.
TDMA:
TDMA technology, which stands for Time Division Multiple Access, is a cell phone standard that has been incorporated into the more advanced GSM standard, which is now the world’s most widely used cell phone technology. TDMA is used in second-generation (2G) cell phone systems such as GSM. Most major third-generation (3G) cell phone systems are primarily based upon GSM rival CDMA. 3G allows for faster data speeds over 2G. While TDMA and CDMA both achieve the same goal, they do so using different methods. TDMA technology works by dividing each digital cellular channel into three time slots for the purpose of increasing the amount of data carried. Multiple users, therefore, can share the same frequency channel without causing interference because the signal is divided into multiple time slots. While each conversation is transmitted alternately over short lengths of time with TDMA technology, CDMA separates communications by code so multiple calls can also be routed into the same channel.
GSM:
GSM, which stands for Global System for Mobile communications, reigns as the world’s most widely used cell phone technology. Cell phones use a cell phone service carrier’s GSM network by searching for cell phone towers in the nearby area. The origins of GSM can be traced back to 1982 when the Groupe Special Mobile (GSM) was created by the European Conference of Postal and Telecommunications Administrations (CEPT) for the purpose of designing a pan-European mobile technology. It is approximated that 80 percent of the world uses GSM technology when placing wireless calls, according to the GSM Association (GSMA), which represents the interests of the worldwide mobile communications industry. This amounts to nearly 3 billion global people. GSM also has the advantage of using SIM (Subscriber Identity Module) cards in the U.S. The SIM card, which acts as your digital identity, is tied to your cell phone service carrier’s network rather than to the handset itself. This allows for easy exchange from one phone to another without new cell phone service activation.
CDMA:
CDMA, or Code Division Multiple Access, is a competing cell phone service technology to GSM, which is the world’s most widely used cell phone standard. CDMA uses a “spread-spectrum” technique whereby electromagnetic energy is spread to allow for a signal with a wider bandwidth. This allows multiple people on multiple cell phones to be “multiplexed” over the same channel to share a bandwidth of frequencies. With CDMA technology, data and voice packets are separated using codes and then transmitted using a wide frequency range. Since more space is often allocated for data with CDMA, this standard became attractive for 3G high-speed mobile Internet use. The CDMA standard was originally designed by Qualcomm in the U.S. and is primarily used in the U.S. and portions of Asia. While CDMA and GSM compete head on in terms of higher bandwidth speed (i.e. for surfing the mobile Web), GSM has more complete global coverage due to roaming and international roaming contracts. GSM technology tends to cover rural areas in the U.S. more completely than CDMA. Over time, CDMA won out over less advanced TDMA technology, which was incorporated into more advanced GSM.
TDMA:
TDMA technology, which stands for Time Division Multiple Access, is a cell phone standard that has been incorporated into the more advanced GSM standard, which is now the world’s most widely used cell phone technology. TDMA is used in second-generation (2G) cell phone systems such as GSM. Most major third-generation (3G) cell phone systems are primarily based upon GSM rival CDMA. 3G allows for faster data speeds over 2G. While TDMA and CDMA both achieve the same goal, they do so using different methods. TDMA technology works by dividing each digital cellular channel into three time slots for the purpose of increasing the amount of data carried. Multiple users, therefore, can share the same frequency channel without causing interference because the signal is divided into multiple time slots. While each conversation is transmitted alternately over short lengths of time with TDMA technology, CDMA separates communications by code so multiple calls can also be routed into the same channel.
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