What is the main difference between GSM & CDMA?

Answers were Sorted based on User's Feedback



What is the main difference between GSM & CDMA?..

Answer / sivakrishna

Gsm-global system for mobile communication.which can takes
place thorugh sim cards.it uses bandwidth in time slots.

cdma-code division multiple access.which uses a code
included in handset.thruogh code communication is takes place.
we cant change ourself from one hand set to other.

Is This Answer Correct ?    34 Yes 9 No

What is the main difference between GSM & CDMA?..

Answer / prathima

In CDMA technology adjacent channel interference is very
low compared to GSM.In cdma the power consumption is very
low it takes 23 to 30 dBm.But in GSM the power consumption
is very high comparitive to CDMA the lower limit is 30 dbm.

Is This Answer Correct ?    28 Yes 7 No

What is the main difference between GSM & CDMA?..

Answer / neeta

GSM:global syetm for mobile communication & CDMA means
code division multiple access.In GSM mobiles we can use sim
card of any compony while we cant do it in CDMA

Is This Answer Correct ?    25 Yes 5 No

What is the main difference between GSM & CDMA?..

Answer / shashi

In cellular service there are two main competing network
technologies: Global System for Mobile Communications (GSM)
and Code Division Multiple Access (CDMA). Cellular carriers
including Sprint PCS, Cingular Wireless, Verizon and T-
Mobile use one or the other. Understanding the difference
between GSM and CDMA will allow you to choose a carrier
that uses the preferable network technology for your needs.
The GSM Association is an international organization
founded in 1987, dedicated to providing, developing, and
overseeing the worldwide wireless standard of GSM. CDMA, a
proprietary standard designed by Qualcomm in the United
States, has been the dominant network standard for North
America and parts of Asia. However, GSM networks continue
to make inroads in the United States, as CDMA networks make
progress in other parts of the world. There are camps on
both sides that firmly believe either GSM or CDMA
architecture is superior to the other. That said, to the
non-invested consumer who simply wants bottom line
information to make a choice, the following considerations
may be helpful.
Coverage: The most important factor is getting service in
the areas you will be using your phone. Upon viewing
competitors' coverage maps you may discover that only GSM
or CDMA carriers offer cellular service in your area. If
so, there is no decision to be made, but most people will
find that they do have a choice.
Data Transfer Speed: With the advent of cellular phones
doing double and triple duty as streaming video devices,
podcast receivers and email devices, speed is important to
those who use the phone for more than making calls. CDMA
has been traditionally faster than GSM, though both
technologies continue to rapidly leapfrog along this path.
Both boast "3G" standards, or 3rd generation technologies.
EVDO, also known as CDMA2000, is CDMA's answer to the need
for speed with a downstream rate of about 2 megabits per
second, though some reports suggest real world speeds are
closer to 300-700 kilobits per second (kbps). This is
comparable to basic DSL. As of fall 2005, EVDO is in the
process of being deployed. It is not available everywhere
and requires a phone that is CDMA2000 ready.
GSM's answer is EDGE (Enhanced Data Rates for GSM
Evolution), which boasts data rates of up to 384 kbps with
real world speeds reported closer to 70-140 kbps. With
added technologies still in the works that include UMTS
(Universal Mobile Telephone Standard) and HSDPA (High Speed
Downlink Packet Access), speeds reportedly increase to
about 275—380 kbps. This technology is also known as W-
CDMA, but is incompatible with CDMA networks. An EDGE-ready
phone is required.
In the case of EVDO, theoretical high traffic can degrade
speed and performance, while the EDGE network is more
susceptible to interference. Both require being within
close range of a cell to get the best speeds, while
performance decreases with distance.
Subscriber Identity Module (SIM) cards: In the United
States only GSM phones use SIM cards. The removable SIM
card allows phones to be instantly activated, interchanged,
swapped out and upgraded, all without carrier intervention.
The SIM itself is tied to the network, rather than the
actual phone. Phones that are card-enabled can be used with
any GSM carrier.
The CDMA equivalent, a R-UIM card, is only available in
parts of Asia but remains on the horizon for the U.S.
market. CDMA carriers in the U.S. require proprietary
handsets that are linked to one carrier only and are not
card-enabled. To upgrade a CDMA phone, the carrier must
deactivate the old phone then activate the new one. The old
phone becomes useless.
Roaming: For the most part, both networks have fairly
concentrated coverage in major cities and along major
highways. GSM carriers, however, have roaming contracts
with other GSM carriers, allowing wider coverage of more
rural areas, generally speaking, often without roaming
charges to the customer. CDMA networks may not cover rural
areas as well as GSM carriers, and though they may contract
with GSM cells for roaming in more rural areas, the charge
to the customer will generally be significantly higher.
International Roaming: If you need to make calls to other
countries, a GSM carrier can offer international roaming,
as GSM networks dominate the world market. If you travel to
other countries you can even use your GSM cell phone
abroad, providing it is a quad-band phone
(850/900/1800/1900 MHz). By purchasing a SIM card with
minutes and a local number in the country you are visiting,
you can make calls against the card to save yourself
international roaming charges from your carrier back home.
CDMA phones that are not card-enabled do not have this
capability, however there are several countries that use
CDMA networks. Check with your CDMA provider for your
specific requirements.
According CDG.org, CDMA networks support over 270 million
subscribers worldwide, while GSM.org tallies up their score
at over 1 billion. As CDMA phones become R-UIM enabled and
roaming contracts between networks improve, integration of
the standards might eventually make differences all but
transparent to the consumer.
The chief GSM carriers in the United States are Cingular
Wireless, recently merged with AT&T Wireless, and T-Mobile
USA. Major CDMA carriers are Sprint PCS, Verizon and Virgin
Mobile. There are also several smaller cellular companies
on both networks.
Code division multiple access (CDMA) is a form of
multiplexing and a method of multiple access to a physical
medium such as a radio channel, where different users use
the medium at the same time thanks to using different code
sequences.
A number of terms are used to refer to CDMA
implementations. The original US standard defined by
QUALCOMM was known as IS-95, where IS refers to an Interim
Standard of the US Telecommunications Industry Association.
IS-95 is often referred to as the second generation (2G)
cellular, or as cdmaOne (the QUALCOMM brand name). CDMA has
been submitted for approval as a mobile air interface
standard to the International Telecommunication Union (ITU).
Whereas the Global System for Mobile Communications (GSM)
standard is a specification of an entire network
infrastructure, the CDMA interface relates only to the air
interface—the radio part of the technology. For example,
GSM specifies an infrastructure based on internationally
approved standard, while CDMA allows each operator to
provide the network features as it finds suited. On the air
interface, the signalling suite (GSM: ISDN SS7) work has
been progressing to harmonise these features.
After a couple of revisions, IS-95 was superseded by the IS-
2000 standard (CDMA2000). This standard was introduced to
meet some of the criteria laid out in the IMT-2000
specification for third generation (3G) cellular. It is
also called 1xRTT which means "1 times Radio Transmission
Technology" because IS-2000 uses the same 1.25 MHz carrier
shared channel as the original IS-95 standard. A related
scheme called 3xRTT uses three 1.25 MHz carriers for a 3.75
MHz bandwidth that would allow higher data burst rates for
an individual user, but the 3xRTT scheme has not been
commercially deployed. More recently, QUALCOMM has led the
creation of a new CDMA-based technology called Evolution-
Data Optimized (1xEV-DO, or IS-856), which provides the
higher packet data transmission rates required by IMT-2000
and desired by wireless network operators.
This CDMA system is frequently confused with a similar but
incompatible technology called Wideband Code Division
Multiple Access (W-CDMA) which is the basis of the W-CDMA
air interface. The W-CDMA air interface is used in the
global 3G standard UMTS and the Japanese 3G standard FOMA,
by NTT DoCoMo and Vodafone; however, the CDMA family of US
national standards (including cdmaOne and CDMA2000) are not
compatible with the W-CDMA family of ITU standards.
Another important application of code division
multiplexing — predating and distinct from CDMA — is the
Global Positioning System (GPS).
The QUALCOMM CDMA system includes very accurate time
signals (usually referenced to a GPS receiver in the cell
base station), so cell phone CDMA-based clocks are an
increasingly popular type of radio clock for use in
computer networks. The main advantage of using CDMA cell
phone signals for reference clock purposes is that they
work better inside buildings, thus often eliminating the
need to mount a GPS antenna outside a building.

Is This Answer Correct ?    62 Yes 44 No

What is the main difference between GSM & CDMA?..

Answer / amit

GSM-gsm is global system of mobile and in gsm ftma and tdma technqs are used.it depends on frequency and yime slot
cdma= scdma is code division multiple aceess technq and use cdma technq.in cdma there is proper code for every channel to set up a call

Is This Answer Correct ?    22 Yes 4 No

What is the main difference between GSM & CDMA?..

Answer / sandhya

what is
the difference between GSM and CDMA, the two leading technologies?
Both GSM (Global System for Mobile Communications) and CDMA (Code
Division Multiple Access) are technologies that work on radio
frequencies, with the mobile phone handset being the antennae receiving
the signal. The range of each technology is different, and they also
have different rates and modulation schemes, and that is why handsets
are different between the two technologies. GSM uses SIM cards
(Subscriber Identity Module) whereas, CDMA based phones do not. In the
case of GSM networks, it is the SIM card that is tied to the network,
where on CDMA networks it is the handset itself that is linked to the
carrier. This means that a SIM card can be placed in pretty much any
handset and still receive GSM coverage, but once a CDMA phone's
subscription has ended, the phone is outmoded. CDMA technology has a
version of the SIM card, the RUIM (Removable User Identity Module) but
is not as widely popular in the US because it is the handsets which
must be linked to the carrier.

Is This Answer Correct ?    17 Yes 7 No

What is the main difference between GSM & CDMA?..

Answer / guest

GSM tends for Global System for mobile communication.It is
based on TDMA & FDMA technique.CDMA is code division
multiple access it is based on multiple access technique.
In this technology the conversation betwwen two user are
coded so it is more secure than GSm.

Is This Answer Correct ?    15 Yes 7 No

What is the main difference between GSM & CDMA?..

Answer / ritika

GSM stands for global system for mobile communication.
In this there is more interuption.
and there is time slots for better utilization.

CDMA stands for code division multiple acess.
In this there is less interuption.
and in this we allocatev a unique code for every user
seprately and allocate bandwidth to user.

Is This Answer Correct ?    8 Yes 0 No

What is the main difference between GSM & CDMA?..

Answer / john

GSM (Global System for Mobile Communications)..............
GSM is the “branded” term referring to a particular use of
TDMA (Time-Division Multiple Access) technology. GSM is the
dominant technology used around the globe and is available
in more than 100 countries. It is the standard for
communication for most of Asia and Europe. GSM operates on
four separate frequencies: You’ll find the 900MHz and
1,800MHz bands in Europe and Asia and the 850MHz and
1,900MHz (sometimes referred to as 1.9GHz) bands in North
America and Latin America. GSM allows for eight
simultaneous calls on the same radio frequency and
uses “narrowband” TDMA, the technology that enables digital
transmissions between a mobile phone and a base station.
With TDMA the frequency band is divided into multiple
channels which are then stacked together into a single
stream, hence the term narrowband. This technology allows
several callers to share the same channel at the same time.

2. CDMA (Code Division Multiple
Access).............................. CDMA takes an
entirely different approach from GSM/TDMA. CDMA spreads
data out over the channel after the channel is digitized.
Multiple calls can then be overlaid on top of one another
across the entire channel, with each assigned its
own “sequence code” to keep the signal distinct. CDMA
offers more efficient use of an analog transmission because
it allows greater frequency reuse, as well as increasing
battery life, improving the rate of dropped calls, and
offering far greater security than GSM/TDMA. For this
reason CDMA has strong support from experts who favor
widespread development of CDMA networks across the globe.
Currently, you will find CDMA mostly in the United States,
Canada, and North and South Korea. (As an interesting
aside, CDMA was actually invented for the military during
World War II for field communications.)

Is This Answer Correct ?    10 Yes 4 No

What is the main difference between GSM & CDMA?..

Answer / kapil

In cellular service there are two main competing network
technologies: Global System for Mobile Communications (GSM)
and Code Division Multiple Access (CDMA). Cellular carriers
including Sprint PCS, Cingular Wireless, Verizon and
T-Mobile use one or the other. Understanding the difference
between GSM and CDMA will allow you to choose a carrier that
uses the preferable network technology for your needs.

The GSM Association is an international organization founded
in 1987, dedicated to providing, developing, and overseeing
the worldwide wireless standard of GSM. CDMA, a proprietary
standard designed by Qualcomm in the United States, has been
the dominant network standard for North America and parts of
Asia. However, GSM networks continue to make inroads in the
United States, as CDMA networks make progress in other parts
of the world. There are camps on both sides that firmly
believe either GSM or CDMA architecture is superior to the
other. That said, to the non-invested consumer who simply
wants bottom line information to make a choice, the
following considerations may be helpful.

Coverage: The most important factor is getting service in
the areas you will be using your phone. Upon viewing
competitors' coverage maps you may discover that only GSM or
CDMA carriers offer cellular service in your area. If so,
there is no decision to be made, but most people will find
that they do have a choice.

Data Transfer Speed: With the advent of cellular phones
doing double and triple duty as streaming video devices,
podcast receivers and email devices, speed is important to
those who use the phone for more than making calls. CDMA has
been traditionally faster than GSM, though both technologies
continue to rapidly leapfrog along this path. Both boast
"3G" standards, or 3rd generation technologies.

EVDO, also known as CDMA2000, is CDMA's answer to the need
for speed with a downstream rate of about 2 megabits per
second, though some reports suggest real world speeds are
closer to 300-700 kilobits per second (kbps). This is
comparable to basic DSL. As of fall 2005, EVDO is in the
process of being deployed. It is not available everywhere
and requires a phone that is CDMA2000 ready.

GSM's answer is EDGE (Enhanced Data Rates for GSM
Evolution), which boasts data rates of up to 384 kbps with
real world speeds reported closer to 70-140 kbps. With added
technologies still in the works that include UMTS (Universal
Mobile Telephone Standard) and HSDPA (High Speed Downlink
Packet Access), speeds reportedly increase to about 275—380
kbps. This technology is also known as W-CDMA, but is
incompatible with CDMA networks. An EDGE-ready phone is
required.

In the case of EVDO, theoretical high traffic can degrade
speed and performance, while the EDGE network is more
susceptible to interference. Both require being within close
range of a cell to get the best speeds, while performance
decreases with distance.

Subscriber Identity Module (SIM) cards: In the United States
only GSM phones use SIM cards. The removable SIM card allows
phones to be instantly activated, interchanged, swapped out
and upgraded, all without carrier intervention. The SIM
itself is tied to the network, rather than the actual phone.
Phones that are card-enabled can be used with any GSM carrier.

The CDMA equivalent, a R-UIM card, is only available in
parts of Asia but remains on the horizon for the U.S.
market. CDMA carriers in the U.S. require proprietary
handsets that are linked to one carrier only and are not
card-enabled. To upgrade a CDMA phone, the carrier must
deactivate the old phone then activate the new one. The old
phone becomes useless.

Roaming: For the most part, both networks have fairly
concentrated coverage in major cities and along major
highways. GSM carriers, however, have roaming contracts with
other GSM carriers, allowing wider coverage of more rural
areas, generally speaking, often without roaming charges to
the customer. CDMA networks may not cover rural areas as
well as GSM carriers, and though they may contract with GSM
cells for roaming in more rural areas, the charge to the
customer will generally be significantly higher.

International Roaming: If you need to make calls to other
countries, a GSM carrier can offer international roaming, as
GSM networks dominate the world market. If you travel to
other countries you can even use your GSM cell phone abroad,
providing it is a quad-band phone (850/900/1800/1900 MHz).
By purchasing a SIM card with minutes and a local number in
the country you are visiting, you can make calls against the
card to save yourself international roaming charges from
your carrier back home. CDMA phones that are not
card-enabled do not have this capability, however there are
several countries that use CDMA networks. Check with your
CDMA provider for your specific requirements.

According CDG.org, CDMA networks support over 270 million
subscribers worldwide, while GSM.org tallies up their score
at over 1 billion. As CDMA phones become R-UIM enabled and
roaming contracts between networks improve, integration of
the standards might eventually make differences all but
transparent to the consumer.

The chief GSM carriers in the United States are Cingular
Wireless, recently merged with AT&T Wireless, and T-Mobile
USA. Major CDMA carriers are Sprint PCS, Verizon and Virgin
Mobile. There are also several smaller cellular companies on
both networks.

Is This Answer Correct ?    14 Yes 8 No

Post New Answer

More GSM Interview Questions

Give me some advantages of GSM?

0 Answers   Ericsson,


Explain the fdd in gsm technology?

0 Answers  


What is the main difference between GSM & CDMA?

73 Answers   BEL, Ericsson, Genpact, HCL, MNC, Nokia, ProtoControl, Reliance, TCS, Teaching, Vodafone,


What is the defference between Rx Lev Sub and Rx Lev Full? What you mean by Link Budget?can you explain

4 Answers   Lucent, NSN, TCS, Zong Pakistan,


Explain about imei in gsm technology?

0 Answers  






Explain tdd in gsm technology?

0 Answers  


What is the difference between rx lev sub and rx lev full?

0 Answers  


we know that the main function of bts is to air interface signaling.but why??????????

2 Answers   Airtel,


Explain drx – trx?

0 Answers  


Explain about lte and gsm internetworking.?

0 Answers  


What is the difference between cdu c and cdu a?

0 Answers  


What is erlangs in gsm technology?

0 Answers  


Categories