There is a lot of confusion between GSM and CDMA technologies. Both are cellular data transmission technologies used in Mobile Communication. To understand them we need a basic foundation of how a technology emerged to push over the other.
History of CDMA: In 1940, Hollywood actress turned inventor, Hedy Lamarr, and co-inventor George Antheil, with World War II situations arising, co-patented a way for torpedoes to be controlled by sending signals over multiple radio frequencies using random patterns. But the U.S. Navy discarded their work as architecturally unfeasible.New York took up the idea, and after the Lamarr-Antheil patent expired, used it to secure communications for the U.S. during the 1962 Cuban Missile Crisis. After becoming an integral part of government security technology, the U.S. military, in the mid-80s, declassified what has now become CDMA technology, a technique based on spread-spectrum technology.
CDMA, incorporating spread-spectrum, works by digitizing multiple conversations, attaching a code known only to the sender and receiver, and then converting the signals into bits and reassembling them. Qualcomm, which was started by a MIT alumni patented CDMA in early 90's began the design of the first CDMA-based cellular base station.But was launched commercially in Hong Kong in 1995.
Advantages of CDMA:
GSM: Just two years before CDMA's 1995 introduction in Hong Kong, European carriers and manufacturers chose to support the first available digital technology - Time Division Multiple Access (TDMA). GSM uses TDMA as its core technology. Therefore, since the majority of wireless users are in Europe and Asia, GSM has taken the worldwide lead as the technology of choice.
Advantages of GSM:
There are around 5 billion GSM users versus CDMA's not reaching even 1 billion figure. CDMA is majorly used in North America while GSM technology is mostly opted in Europe, Middle East and Africa.
Parameter to Decide Which One is Best:
CDMA: While using CDMA Your account information is programmed into your cellular phone. If you want to change your phone, you have to contact your carrier and have them reprogram your new phone. You will also need to re-enter your contact list and calendar information into your new phone.
GSM: Your account information along with your contact list and other personal data are stored on a SIM card (Subscriber Identity Module). It is a small chip you can freely remove from your phone. When you get a new mobile device, you can simply insert your SIM card into it and it will work with your current account information and contact list.
So here GSM is clear winner.
History of CDMA: In 1940, Hollywood actress turned inventor, Hedy Lamarr, and co-inventor George Antheil, with World War II situations arising, co-patented a way for torpedoes to be controlled by sending signals over multiple radio frequencies using random patterns. But the U.S. Navy discarded their work as architecturally unfeasible.New York took up the idea, and after the Lamarr-Antheil patent expired, used it to secure communications for the U.S. during the 1962 Cuban Missile Crisis. After becoming an integral part of government security technology, the U.S. military, in the mid-80s, declassified what has now become CDMA technology, a technique based on spread-spectrum technology.
CDMA, incorporating spread-spectrum, works by digitizing multiple conversations, attaching a code known only to the sender and receiver, and then converting the signals into bits and reassembling them. Qualcomm, which was started by a MIT alumni patented CDMA in early 90's began the design of the first CDMA-based cellular base station.But was launched commercially in Hong Kong in 1995.
Advantages of CDMA:
- Increased cellular communications security.
- Simultaneous conversations.
- Increased efficiency, meaning that the carrier can serve more subscribers.
- Size of Phones became smaller.
- Low power requirements and little cell-to-cell coordination needed by operators.
- Extended reach - beneficial to rural users situated far from cells.
GSM: Just two years before CDMA's 1995 introduction in Hong Kong, European carriers and manufacturers chose to support the first available digital technology - Time Division Multiple Access (TDMA). GSM uses TDMA as its core technology. Therefore, since the majority of wireless users are in Europe and Asia, GSM has taken the worldwide lead as the technology of choice.
Advantages of GSM:
- International roaming permits subscribers to use one phone throughout Western Europe. CDMA will work in North America, but not France, Germany, the U.K. and other popular European destinations.
- GSM is mature, having started in the mid-80s. This maturity means a more stable network with robust features. CDMA is still building its network.
- GSM's maturity means engineers cut their teeth on the technology, creating an unconscious preference.
- The availability of Subscriber Identity Modules, which are smart cards that provide secure data encryption give GSM m-commerce advantages.
There are around 5 billion GSM users versus CDMA's not reaching even 1 billion figure. CDMA is majorly used in North America while GSM technology is mostly opted in Europe, Middle East and Africa.
Parameter to Decide Which One is Best:
CDMA: While using CDMA Your account information is programmed into your cellular phone. If you want to change your phone, you have to contact your carrier and have them reprogram your new phone. You will also need to re-enter your contact list and calendar information into your new phone.
GSM: Your account information along with your contact list and other personal data are stored on a SIM card (Subscriber Identity Module). It is a small chip you can freely remove from your phone. When you get a new mobile device, you can simply insert your SIM card into it and it will work with your current account information and contact list.
So here GSM is clear winner.
