Information Technology

What is GSM and CDMA, Check Detailed Caparison

What is GSM and CDMA, Check Detailed Caparison
Written by

We all use mobile phones but do you know whether you have a mobile GSM or CDMA. After all, what is GSM and CDMA (Difference between GSM and CDMA). Today, mobile phones are being used by crores of people in almost all places in the world. The reality is that the mobile phone has changed the definition of communication service. It is one of the fastest-growing in the telecommunication industry.

In today’s digital world mobile phone is like a boon for humans. But do you know that voice transmission is mainly done in two ways, one is GSM and the other is CDMA technology? Today, in this article, we will get to know about these two technologies GSM and CDMA and how it works. So, let’s start delaying and know what GSM and CDMA are and how it works.

What is GSM –

The full form of GSM is Global System for Mobiles. This is a worldwide standard digital cellular telephony. GSM was created by Europeans, it was given a published standard status by ETSI in 1982. And later it was used in countries around the world.

GSM technology was first introduced in Finland in 1991. Today, more than 690 mobile networks are providing GSM service in 213 countries. Which means that around 82.4% of the global mobile connection is GSM only. GSM World says that today there are about 2 billion GSM mobile users worldwide. If we talk about the data of different countries, the first name in this list comes from China where 370 million users use GSM mobile phone, followed by Russia where 145 Million and third place in India where 83 Millions of people use it.

Features of GSM Technology –

If we talk about the features of GSM technology, then there are many features of it which I have mentioned below so that you are easy to understand.

  • GSM Phone is a digital cellular technology that is used to transmit or send mobile voice and data services.
  • In GSM, the narrowband Time Division Multiple Access (TDMA) technique is used to transmit signals.
  • A circuit-switched is used which divides all 200kHz channels into 8 25kHz time slots.
  • GSM network mainly operates in mobile communication bands of 900MHz and 1800MHz all over the world.
  • GSM Network mainly consists of three parts: the Switching System (SS), the Base Station System (BSS) and the Operation and Support System (OSS).
  • The Switching System (SS) is responsible for carrying out call processing and subscriber related function.
  • All radio-related function is performed by BSS, and it mainly consists of two things Base Station Controller (BSCs) and Base Transceiver Stations (BTSs).
  • Its Operation and Support System work is that they provide a network overview and support all maintenance operations.

What is CDMA –

The full form of CDMA is Code Division Multiple Access. This is a digital cellular technology that uses the spread spectrum technique. Unlike other technology, GSM which uses TDMA, unlike CDMA, no one is assigned to a specific frequency user. Rather all channels use the full available spectrum.


Security is given a lot of attention here. All individual conversations are encoded using a pseudo-random digital sequence. Compared to other digital cellular technology, it provides better data and voice communication, and more and more users can connect at a time. This is a common platform where 3G technologies have been created.

CDMA is a military technology that was first used by the British against Germans during the Second World War. It was used to jam the transmission so that they cannot send static signals. A company named Qualcomm designed the communication chip for CDMA technology. And when this information became public, Qualcomm filed its patent on it and became the first company to commercialize it.

Features of CDMA Technology –

If we talk about the features of CDMA technology, then there are many features of it which I have mentioned below so that you are easy to understand.

  • CDMA is a type of multiplexing that enables many signals to occupy a single transmission. This increases the efficiency of using bandwidth completely.
  • This is a type of technique also called spread spectrum technique that allows many users to occupy a fixed space, band at the same time and frequency simultaneously.
  • Individual conversations are encoded with the help of a pseudo-random digital sequence.
  • This technology is used in the ultra-high-frequency (UHF) cellular telephone system, where the band range is from 800MHz to 1.9GHz.
  • This technology is quite different from other technology such as Time Division Multiple Access and Frequency Division Multiple Access. Here the user has full bandwidth, full-time access.
  • The basic principle of CDMA is that different CDMA codes are used to differentiate different users.
  • The technique used here is Direct Sequence Spread Spectrum Modulation (DS-CDMA), Frequency Hoping or Mixed CDMA detection (JDCDMA).
  • Here when the signal is generated, it is extended over the entire bandwidth. This is done by using a code, also called a Spreading Code.
  • By using a group of codes that are orthogonal to each other, it is possible that we can recognize a signal that has a constant code, within other orthogonal codes.

Also read – 

Difference Between GSM and CDMA

Technology –

  • CDMA is based on Spread Spectrum technology which makes full use of available bandwidth. This allows each user to transfer across the entire frequency spectrum.
  • GSM is based on the wedge spectrum which is also known as Carrier. This carrier is divided into multiple time slots and each user is given a different time slot, and until
    The ongoing call does not end, no other subscriber can use it.
  • GSM uses both techniques TDMA and FDMA for the user and cell separation. TDMA provides multi-user access by dividing the channel into different time slices, while FDMA provides multi-user access by separating the used frequencies.

Security – 

  • More security is achieved in CDMA technology as compared to GSM because encryption is inbuilt in CDMA.
  • All users are provided with unique code and all conversations are encoded for CDMA users with more security level.
  • It is not so easy to trace the signal in CDMA as compared to GSM because it is focused in a narrow bandwidth.
  • That is why CDMA phone calls are much more secure than GSM.

SIM Cards –

  • A GSM phone needs a specialized card which is also called SIM (Subscriber Identity Module). These are SIM carrier-specific and can be changed from one phone to another without loss of any data.
  • SIM cards are not required in CDMA devices, instead, they depend on ESNs (Electronic Serial Numbers).
  • If you have to activate the phone in CDMA phone then the user will have to call their Carrier or use an online system for ‘ESN’ change. Due to the absence of a SIM card here, device swapping is very difficult.

Flexibility –

  • GSM is more flexible than CDMA. Here SIM card can be easily changed from one mobile to another. CDMA will only work if registered in the ESN database.
  • If the CDMA phone is turned off, then you have to buy a new phone, there is no need to do so in GSM.

Spectrum Frequencies –

  • CDMA Network CDMA works in the frequency spectrum of 850MHz and 1900MHz.
  • GSM Network GSM works in the frequency spectrum of 850MHz and 1900MHz.

Radiation Exposure –

  • GSM phones have more radiation because they emit continuous wave pulses, due to which there is a need to reduce these radiations.
  • CDMA phones do not emit much radiation. If compared, GSM phones emit 28 times more than CDMA phones. This is why GSM Phones are more biologically reactive than CDMA.

Global reach –

  • GSM is used in more than 80% of mobile networks across the world, whereas CDMA is used only in select few places.
  • Both technologies are used in 3G standard phones, but 3G GSM Speed ​​is faster than 3G CDMA Speed.

Conclusion – 

I sincerely hope that I have given you complete information about what is GSM and CDMA  and I hope you all have understood about GSM and CDMA. I request all of you readers that you too should share this information in your neighbourhood, relatives and friends so that there will be awareness among us and it will benefit everyone. I need your support so that I can convey more new information to you.

It has always been my endeavour that I always help my readers or readers from all sides, if you people have any doubt of any kind, then you can ask me irresponsibly. I will definitely try to solve those Doubts. How did you like this article CDMA and GSM, please tell us by writing a comment so that we too have a chance to learn something from your ideas and improve something.

“My country is changing and moving forward

About the author

NIKIT KESHARWANI is the founder of and many other online ventures. He is blogging since the age of 15. Writing has always been at the center of his life and the passion for technology and gadgets that he developed over the years influenced him to start TECHNO-PRO.IN

1 Comment

Leave a Comment