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IS-95 is the first CDMA based digital cellular standard by Qualcomm. CDMA2000 denotes a family of standards of underlying technology that is a registered trademark of TIA-USA, and is based on the technology of IS-95.
For information on IS-95 and CDMA2000 system architecture, visit the Related Links.
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CDMA2000 is a 3G mobile carrier technology providing voice and data services across wireless networks. 3G is known to provide a high quality voice and high speed data. It has now been exceeded by 4G which provides an even faster service.
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3G is 3rd generation mobile technology. UMTS is one of the technologies under 3G, just like CDMA2000.
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Basic answer - No.
The blackberry 8530 uses the CDMA2000 1xEV-DO radio transmission method. You would need to find a cellular network that operates using that transmission method.
AT&T uses GSM and UMTS.
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According to gsmarena.com, the Storm is compatible with the following, making it technically (theoretically) compatible with AT&T:
2G Network: GSM 850 / 900 / 1800 / 1900
3G Network: HSDPA 2100 | CDMA2000 1x EV-DO (Verizon)
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EV has different meaning in different domains.
Since the question has been asked in PDA and handheld computers section, for the mobile computers and PDA phones EV or more precisely EV-DO stands for EVolution-Data Only, which is a 3G high-speed digital data access service provided by mobile cellular phone companies. It uses the CDMA technology (it is part of the CDMA2000 standard). The equipment should have an EV-DO modem to access this service.
- Neeraj Sharma
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2G, 3G, 3.5G refer to the speeds at which the mobile device can access the Internet. Since the mobile devices have matured over time, these are also referred to 2 generation, 3 generation and so on. In general, the higher the number the better is the data transfer speed. Please find more details...
2G networks were built mainly for voice services and slow data transmission. These are still prevalent in less developed telecom markets.
3G is a family of standards for mobile telecommunications, which includes UMTS, and CDMA2000 as well as the non-mobile wireless standards DECT and WiMAX. Compared to 2G and 2.5G services, 3G allows simultaneous use of speech and data services and higher data rates (at least 200 kbit/s peak bit rate to fulfill to IMT-2000 specification). Today's 3G systems can in practice offer up to 14.0 Mbit/s on the downlink and 5.8 Mbit/s on the uplink.
3.5G is an enhanced 3G protocol - High-Speed Downlink Packet Access (HSDPA). This protocol belongs to the High-Speed Packet Access (HSPA) family, which allows networks based on Universal Mobile Telecommunications System (UMTS) to have higher data transfer speeds and capacity.
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Wireless LAN
Wireless WAN
Coverage
Office Buildings or Campus with
some public hotspots
Available wherever there is cellular
network coverage; nationwide and
global
Throughput
Speeds
1--5 Mbps (However the
underlying Internet connection
may yield a slower speed)
30--50 kbps (GPRS)
40--70 kbps (CDMA2000 1X)
Security
Security flaws
Secure encryption and
authentication
Airtime Charges
Airtime charges exist for most
Hotspot access. No airtime
charges for office or home users
(although ISP monthly service
fee still exists).
Monthly subscription from wireless
network provider
Uses
• Accessing a shared network
within a building or across a
campus
• Remote access to a corporate
network for e-mail and
applications
• Web and internet access.
Voice
No
Yes
Wired analogy
Ethernet Network
Remote modem access
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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.
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2G is the GSM specification used to enhance the mobile whereas 3G communications is used for mobile users to have communication over voice with added Multimedia Applications with proportionate speed as well..,http://bit.ly/ouNC5C
First, about cellular generations. Having worked in the industry for a while, I have a narrower view what 1G, 2G, 3G, 4G, etc. mean. First 1G service was based on a TDM voice infrastructure -- built around class x switches and 64 kbps slots. It had data, but circuit switched over a 64Kpbs voice bearer.
Second, 2G service had the same switched TDM backbone, but added a true Data Bearer and a digital voice bearer. Data rates were still limited to the max 64kbps of a single time slot.
2.5G added a packet bearer to the mix, still limited to 64kbps slots.
Third generation (3G) changed the backbone slightly to allow a full T1 or E1 or J1 to be consumed by a data sub-scriber, but is still based on an ISDN style backbone. Sure you have packet switched data, but its carried over a traditional TDM backbone. There still a circuit voice backbone and while the data rates are high enough for VoIP, the latency of the data service is to great to base all of the "bearer services" on it, so you still have circuit voice, circuit data and packet data bearers.
Finally, 4G systems will utilize a packet infrastructure rather than a traditional telephone architecture. Services will be horizontally layered on top of a proper low latency, QoS enabled packet switch (read IP) infrastructure. Gone will be the circuit voice and circuit data bearers.
So "G" has more to do with the infra-structure and less to do with the data rates. The data rates over the air are driven by the organization of the infrastructure and other than that have little to do with what generation they are.
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CDMA is Code Division Multiple Access.The word itself explains that multiple users accessing the same carrier frequency but having their unique code for each one. Here the overlapping of messages takes place.
GSM is a technique that works under TDMA,which Time Division Multiple Access.GSM
Global Service For Mobile Communication. users having the same carrier frequency with different time slots.Most of the mobile phones which is 2G having frequency of 900MHZ to 1800MHZ.for 3G it operates at2100MHZ.
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International Mobile Telecommunications-2000 (IMT-2000), better known as 3G or 3rd Generation, is a family of standards for mobile telecommunications fulfilling specifications by the International Telecommunication Union,[1] which includes UMTS, and CDMA2000 as well as the non-mobile wireless standards DECT and WiMAX. While the GSM EDGE standard also fulfils the IMT-2000 specification, EDGE phones are typically not branded 3G. Services include wide-area wireless voice telephone, video calls, and wireless data, all in a mobile environment. Compared to 2G and 2.5G services, 3G allows simultaneous use of speech and data services and higher data rates (at least 200 kbit/s peak bit rate to fulfill to IMT-2000 specification). Today's 3G systems can offer practice of up to 14.0 Mbit/s on the downlink and 5.8 Mbit/s on the uplink.
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While a lot of attention has been placed on the growing standards war for next generation wireless network standards between LTE and WiMAX - for instance see here and here - a number of interesting developments have been made regarding the Chinese developed outsider TD-LTE.
TD-LTE is a standard for wireless mobile networks and 4G candidate which has been developed by China Mobile, building upon the TD-SCDMA 3G standard. The TD-LTE stems from China's indigenous innovation policy which seeks to reduce China's reliance upon foreign IPR by supporting the use of domestic alternatives. (Don't miss the upcoming Talkstandards open forum for further discussion on China's standards policy).
The TD-LTE standard has been submitted, along with 5 other competing standards including LTE and WiMAX, to the International Telecommunications Union (ITU) for consideration for inclusion in the 4G family and Zhao Houlin, ITU deputy secretary-general, has commented that:
"I am confident about the market application of TD-LTE around the world, and it has a 70 percent possibility to be chosen as the 4G standard."
TD-LTE is interesting in that it bridges the gap between LTE and WiMAX. While based upon the same 3GPP package as LTE, it differs in the method of "duplex", which is how devices communicate in two directions - receiving and transiting data simultaneously. While the LTE supported in Europe and the US uses Frequency-Division Duplexing (FDD) TD-LTE uses an alternative method called Time-Division Duplexing (TDD) which is also the same approach used by the IEEE 802.16 standard upon which WiMAX is based. Furthermore, TD-LTE utilizes cheaper and less congested radio spectrum compared to LTE.
Simply speaking FDD uses paired spectrum with two channels, designating one each for upload and download, while TDD uses unpaired spectrum channels that combines upload and download and distributes the resources based on real-time demand. As such, FDD is best utilized by voice calling in which both upload and download are symmetrical, while TDD is advantageous for use with data traffic, which is asymmetric.
The result of this is that due to the similarities between LTE and TD-LTE, both technologies can be supported by a single chip-set while the towers designed for WiMAX can be upgraded for use with TD-LTE at relatively low cost. So while there is considerable interoperability between the LTE and WiMAX standards, TD-LTE indirectly circumvents the present divide.
However aside from TD-LTE merely ending up a setting on multi-mode devices, the standard is expected to see deployment outside of China in the near future. It has beenannounced that Qualcomm has won significant slabs of unpaired spectrum in India for US $1.07 billion (~ € 874 million), in which the company plans to launch a TD-LTE compliant network. Similarly, despite China remaining in the early stages of a full scale rollout of 3G, China Mobile appears egger to "leapfrog" to 4G due to the weakness of the Chinese proprietary TD-SCDMA compared to W-CDMA and CDMA2000.
Deployment of the technology in both China and India, which together make up 40% of the world population, will surely be a great boost for the standard. The changing global economy is bringing an increasing importance to the mobile markets of China and India, which represent both the world's largest uninterrupted mobile market and the world's fastest growing mobile market respectively. Moreover, as the standard can operate on the same chip set as LTE, there will be no lack of compliant handsets which will favor a wide uptake.
If the not so successful TD-SCDMA in any way acts as an indicator for the success of TD-LTE, outlooks are bleak. But the Chinese standard is bound to gain a strong foothold in the developing world, while LTE is deployed in Europe and the US. There is a significant compatibility between the two and TD-LTE's edge lies in the lower cost TDD spectrum. It is this fact that raises the probability of China succeeding to export a mature ICT standard from the developing to the West.
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