GSM (Global System for Mobile Communication)
and CDMA (Code Division Multiple Access) are
two dominant technologies for mobile
communication. These two technologies differ in
the way calls and data travel over the mobile
phone networks take place. On comparing both
the technologies GSM has some limitation when
the call quality is concerned but still has more
flexibility and an easy implementation relative to
the CDMA technology . The major difference
between the two lies in terms of the technology
they use, security factors, their global reach and
the data transfer speeds.
1. Technology
The CDMA is based on spread spectrum
technology which makes the optimal use of
available bandwidth. It allows each user to
transmit over the entire frequency spectrum all
the time. On the other hand GSM operates on the
wedge spectrum called a carrier. This carrier is
divided into a number of time slots and each user
is assigned a different time slot so that until the
ongoing call is finished, no other subscriber can
have access to this. GSM uses both Time Division
Multiple Access (TDMA) and Frequency Division
Multiple Access (FDMA) for user and cell
separation. TDMA provides multiuser access by
chopping up the channel into different time slices
and FDMA provides multiuser access by
separating the used frequencies.
2. Security
More security is provided in CDMA technology as
compared with the GSM technology as encryption
is inbuilt in the CDMA. A unique code is provided
to every user and all the conversation between
two users are encoded ensuring a greater level of
security for CDMA users. The signal cannot be
detected easily in CDMA as compared to the
signals of GSM, which are concentrated in the
narrow bandwidth. Therefore, the CDMA phone
calls are more secure than the GSM calls. In
terms of encryption the GSM technology has to
be upgraded so as to make it operate more
securely.
3. Spectrum Frequencies
The CDMA network operates in the frequency
spectrum of CDMA 850 MHz and 1900 MHz while
the GSM network operates in the frequency
spectrum of GSM 850 MHz and 1900 MHz.
4. Global Reach
GSM is in use over 80% of the world’s mobile
networks in over 210 countries as compared to
CDMA. CDMA is almost exclusively used in United
States and some parts of Canada and Japan. As
the European Union permissions GSM use, so
CDMA is not supported in Europe. In North
America, especially in rural areas, more coverage
is offered by CDMA as compared to GSM. As
GSM is an international standard, so it’s better to
use GSM in international roaming. GSM is in use
by 76% of users as compared to CDMA which is
in use by 24% users.
5. Data Transfer Rate
CDMA has faster data rate as compared to GSM
as EVDO data transfer technology is used in
CDMA which offers a maximum download speed
of 2 mbps. EVDO ready mobile phones are
required to use this technology. GSM uses EDGE
data transfer technology that has a maximum
download speed of 384 kbps which is slower as
compared to CDMA. For browsing the web, to
watch videos and to download music, CDMA is
better choice as compared to GSM. So CDMA is
known to cover more area with fewer towers.
6. Radiation Exposure
GSM phones emit continuous wave pulses, so
there is a large need to reduce the exposures to
electromagnetic fields focused on cell phones with
“continuous wave pulses”. On the other hand
CDMA cell phones do not produce these pulses.
GSM phones emit about 28 times more radiation
on average as compared to CDMA phones.
Moreover, GSM phones are more biologically
reactive as compared to CDMA.

www.engineersgarage.com/contribution/difference-between-gsm-and-cdma

Insightful.

Thanks.

moshoodn: Insightful.

Thanks.

thanks bro.

Cool..

Me likey..

Quite unfortunate our CDMA operatot can't keep up to compete with the Gsm counterpart

Warlord3000: Cool..

Me likey..

Quite unfortunate our CDMA operatot can't keep up to compete with the Gsm counterpart

yes,the major reason is dat we are a one band wagon country.we like d same thing.over there in The US,its not so and d are more conscious security wise than us.if u check it out,d health hazard dat emanate from gsm is more compare to cdma,but we no send
but in reality,cdma is better dan gsm even interms of data connectivity

Itoroetti:

yes,the major reason is dat we are a one band wagon country.we like d same thing.over there in The US,its not so and d are more conscious security wise than us.if u check it out,d health hazard dat emanate from gsm is more compare to cdma,but we no send
but in reality,cdma is better dan gsm even interms of data connectivity

i don't necessarily think that gsm is worse or better than CDMA. They have both been competing standards over the years. Thankfully the interest groups on both sides have adopted a unified data technology for 4G:- LTE (which is gsm/umts based). This is good going forward as it promotes better interoperability. Voice is still on either the respective gsm or CDMA platforms but data is mostly migrating to LTE