What is CDMA mobile?
Code division multiple access (CDMA) is the current name for the cellular technology originally known as IS-95. This technology is in competition with the GSM technology set for leadership in the global cellular technology market. Developed originally by Qualcomm and enhanced by Ericsson, CDMA is characterized by its high capacity and small cell radius, employing spread-spectrum technology and a special coding scheme (using which each transmitter is assigned a code). By contrast, time division multiple access divides access by time, while frequency-division multiple access divides it by frequency. CDMA is a form of "spread-spectrum" signaling, since the modulated coded signal has a much higher bandwidth than the data being communicated.
An analogy to the problem of multiple access is a room (channel) in which people wish to communicate with each other. To avoid confusion, people could take turns speaking (time division), speak at different pitches (frequency division), or speak in different directions (spatial division). In CDMA, they would speak different languages. People speaking the same language can understand each other, but not other people. Similarly, in radio CDMA, each group of users is given a shared code. Many codes occupy the same channel, but only users associated with a particular code can understand each other.
CDMA also refers to digital cellular telephony systems that use this multiple access scheme, such as those pioneered by QUALCOMM, and W-CDMA by the International Telecommunication Union (ITU).
CDMA has been used in many communications and navigation systems, including the Global Positioning System and in the OmniTRACS satellite system for transportation logistics.
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( C ode D ivision M ultiple A ccess) A method for transmitting simultaneous signals over a shared portion of the spectrum. The foremost application of CDMA is the digital cellular phone technology from QUALCOMM that operates in the 800MHz band and 1.9GHz PCS band. CDMA phones are noted for their …call quality. ( Full Answer )
When we are talking on landline phone if a call comes in on a mobile phone there is some disturbance on the landline but this does not happen with CDMA phone why?
Answer . That noise is the digital modulation on the high power RF signal that is induced on the rear end of the phone instruments audio circuit the same disturbance will be heard on any audio instrument like a CD player or a HiFi system if a cell is used close to it.
No, not possible. You can get outgoing call log list, if you are postpaid customer. But, one way to get incoming and outgoing call log list; simple you should carry one FRI copy from Police Department and submit at reliance customer care.
Code Division Multiple Access can allow for multiple levels ofconversation at the same time on different lines of communication.It does this by first using conventional modulation practices, thenby applying a special digital modulation technique known as SpreadSpectrum.Ã It allows for spectral ef…ficiency, voice encoding andsuperior coverage. ( Full Answer )
This depends on where you are, but 9 times out of 10 CDMA will provide better coverage than GSM, especially inside buildings that GSM can't penetrate. GSM= work with SIMcards ( ATT,T-mobile) some areas have better coverage than CDMA (Verizon, Sprint, Alltel ect), the Problem with GSM is that its b…andwith is not as fast as CDMA since Data travels quicker on CDMA's devices due to less steps to follow : GSM= Data - SIMcard - device= response CDMA= Data - Device= Response (wider bandwith as well) so i would say that CDMA is better than GSM. Although it has been very widely reported that GSM carriers have faster speeds than CDMA carriers. Such as AT&T has far faster speeds than CDMA networks while covered. ( Full Answer )
There is no such thing as a CDMA SIM card, since CDMA phones do not use SIM cards.
The iPhone 4S is an international phone which runs on CDMA. Tech specs can be found here http://www.apple.com/iphone/specs.html
CDMA is Code-Division Multiple Access abbreviation, full known as Code Division Multiple Access, is a more advanced digital interface technology, which is characterized by a high frequency of utilization, mobile low power consumption, good quality voice calls. 2. Compared with GSM phones, CDMA mobil…e phone has the following advantages: First, the transmission power is extremely small, so conversation is not only less radiation, but also longer battery life mobile phones.. Second, the use of advanced soft-switching technology allows mobile phone is not GSM phones are dropped.. Third, better call quality, almost no noise when making a call, in the case of large background noise, you can also get a better call quality.. Fourth, a high put-through rate. As military interference from CDMA systems, and the signal occupy the entire band, almost an ordinary narrow-band modulation efficiency of seven times, so for the same bandwidth, CDMA system is the GSM system capacity of 4 to 5 times the extent of its mesh-plug a significant decrease in Therefore, uptake rates are much higher. 3. Ordinary GSM and analog mobile phone power 600 milliwatts under the general control, while the CDMA system, the maximum is only 200 mW transmit power, general power can be controlled at 0:00 call a few milliwatts, its radiation is negligible, there is no health adverse effects. As the base station and mobile transmit power reduction, so handset talk-time will be greatly extended battery life phone will also be extended to protect the environment played a role, it is called the "green phone.". ( Full Answer )
You must either take the phone into the cellular providers store or call them and they will direct you thorugh the process. It merely consists of punching in numbers.
i have the Motorola q cdma, that's what the version i have is called... so no not all are called that there is also the q9m and q9c i think i might have the 9qc im not sure...
in cdma The near-far problem is a condition in which a receiver captures a strong signal and thereby makes it impossible for the receiver to detect a weaker signal
Code Division Multiple Access ( CDMA ) is a channel access method used by various radio communication technologies. By contrast, time division multiple access ( TDMA ) divides access by time, while frequency-division multiple access ( FDMA ) divides it by frequency. CDMA is a form of spread-spe…ctrum signaling, since the modulated coded signal has a much higher data bandwidth than the data being communicated. ( Full Answer )
Full form of CDMA is code divison multiple access and full form of GSM is Global system for mobile communications.
CDMA is a type of network that cell phone company's use. There are to meager types of networks that are used CDMA and GSM. Cell phone are usally made to work on one or the other network. The Iphone is GSM and Verizons Dare is CDMA but some phone can work on both like the new Blackberry storm.
GSM phones have sim cards that contain your information and can be transferred between phones, and cdma phones store the information in the phone itself. The two networks are not compatible with each other so phones cant be switched between the two
There are compatible with both GSM and CDMA. These phones are often called "quad-band" phones, because they can operate in four different bands.
CDMA is used by Verizon and Sprint. That technology only works in the USA. It doesn't use sim cards, so upgrading can be a little more difficult. GSM is used by AT&T and T-Mobile. The technology works world-wide. They use sim cards making it easier for upgrading your phone. On BIG upside of GSM i…s that you can talk and surf the web at the same time.** ** Ex. You are using headphones for the call and you need to check something on the web, you can then use data (web, navigation, etc.) while the phone call is going on. ( Full Answer )
A CDMA repeater is a device that extends the signal range for cell phone providers that use the CDMA technology. CDMA (Code Division Multiple Access) is one of the technologies cell phone companies use for their phone service. More information on CDMA is available here:. http://en.wikipedia.org/wik…i/CDMA ( Full Answer )
1. Their abbreviation meanings actually give light to the manner they optimize channels. TDMA is short for Time-Division Multiple Access while CDMA is for Code-Division Multiple Access. 2. TDMA emerged and was utilized first. CDMA is the more recent technology gradually replacing TDMA. 3. TDMA …chops or divides the channel into sequential time portions as each user has its respective right turn for channel use. 4. CDMA uses a process called Spread Spectrum '" scattering of digital bits in pseudo-random manner and collecting them for interpretation. 5. CDMA allows numerous users to use the channel at the same time while TDMA does not. ( Full Answer )
There is no such thing as a CDMA SIM card.CDMA is a technology which doesnt use SIM cards.And WCDMA is evolved from gsm and uses SIM cards for 3g.
\nSignal Coverage - drive through a long tunnel or ride a lift and your phone's dead.\n. \nOther ones could be -\n. \nNo Data Packet Access in simple CDMA (e.g. you can browse the net' on your phone)\n. \nLess Users - More Cells needed to service people. Remember the old problem of sending an SMS… and it taking ages for it to go through?\n. \nHappy to help\n. \n'Matt ( Full Answer )
Disadvantages to CDMA are Your handset can only be used with the provider that you got the phone from. Should your phone brake under contract but out of warranty, getting a new phone from the provider will automatically extend your contract another 2 years. CDMA is limited to North America and a f…ew other places, GSM is worldwide. If you like to travel oversea's, for the most part, leave your CDMA phone at home. GSM phones can be unlocked meaning that they can be used with any GSM provider. If my GSM phone brakes, I can get a cheap replacement phone without having to extend my contract. When I travel oversea's, I can continue using my service, better yet, I can use a local sim card for the country I am in and make and receive calls at a much lower rate. ( Full Answer )
CDMA can only be used in North America. If one breaks a phone while not under contract but not under warranty, getting a replacement from the provider will automatically extend the contract by two years.
It depends if the phone is compatible with a gsm network if so it has to be unlocked
- CDMA800 (low band) is at freq 800MHz whereas CDMA1900 (high band) is at 1900MHz. . - TX power of CDMA800 is lower than the CDMA1900.
Boost mobile has two types of service, CDMA and IDEN. So technically its CDMA and TDMA, they do not have GSM service.
In CDMA all the stations can sends data simultaneously. But in FDMA only one channel occupies the entire bandwidth of the link so each channel can be assigned to only one user at a time. So CDMA is better than FDMA.
800 mhz & 1.8 ghz - This was the first answer given. Hertz is a measurement of the speed of a transmission with respect to electrical wave produced. A technique is then used by the sending and receiving device to transmit data on the waves produced. This can be from 1 to many bits per wave. If a tr…ansmission is made on a square wave on the rising and falling edge, then that would be 2 bits per wave. If the wave was produced a thousand times per second, that would be 2,000 bits per second and that would be the bandwidth. The bandwidth is the multiplication of the speed of the wave in Hertz (capitalised as it is a person's surname) and the amount of bits transferred per wave. A network cable working at 100Mbps, transfers 100 million bits per second, but does not necessarily have a wave running at 100MHz with one bit per wave. i.e. Cat 4 TP implemented as Fast Ethernet. The bandwidth of EDGE, which is an enhancement of GPS is 384Kbps CDMA is a competing technology to GPS and is, as far as I am aware, better than this because it distributes the call data in a different way. The base speed is 9.6Kbps, which is the same a GPS. Voice is tranmitted at 8Kbps. All the connections share the Spread Spectrum used by CDMA allowing up to 1.23Mbps, allowing up to 131 simultaneous connections as opposed to 48 GSM connection at a similar bandwidth of 1.23Mbps, however GPS does not support this bandwidth, so less connections are allowed simultaneously ( Full Answer )
yes...absolutely CDMA phones only allow certain sim....and tata indicom is one of them people usually take CDMA phone for tata indicom and its converse is also true
Some popular brands like RIM Blackberry, Samsung, Sony Ericsson, Motorola, LG have phone models that are offered on GSM carriers and they also have phones offered on CDMA carriers, however, if you want to know what phone models have both GSM and CDMA technology, then some examples are the Blackberry… Storm 1, Blackberry Storm 2, and Blackberry Tour. ( Full Answer )
\n â¢ In 1989, the Telecommunications Industry Association (TIA) endorsed a digital technology called Time Division Multiple Access (TDMA ). Just three months later, Qualcomm introduced Code Division Multiple Access (CDMA) , a superior technology for wireless and data products that …changed the global face of wireless communications forever. . ( Full Answer )
cdma 450 used RUM card cdma 800 used code cdma 450 frequency has very large circle cdma 800 frequency has normal circle
CDMA-(code division multiple access), uses spread spectrum technique, which spreads the bandwidth of the data uniformly for the same transmitted power. (surce:wikipedia)
In the CDMA technology It is either between your Handset and the Mobile Station. The dedicated frequency are allocated for u sending your data to the mobile station (Uplink freuency) and a dedicated frequency is reserved for you to receive your data from the mobile station (Downlink frequency)
There is no such thing as a CDMA card so there is no card for a CDMA device to accept. With a CDMA device you have to contact the service provider and give them the new device's ESN and once they have that changed in their system they will walk you through manually programming your new device.
If there is a place for a SIM card under the battery then the device is GSM. If there is not a place for a SIM card then it is CDMA. Also, if there is an ESN on the bar code label under the battery then it is also CDMA. If there is an IMEI on the bar code label then it is GSM.
Brief Working of CDMA CDMA takes an entirely different approach from TDMA. CDMA, afterdigitizing data, spreads it out over the entire available bandwidth. Multiplecalls are overlaid on each other on the channel, with each assigned a unique sequencecode. CDMA is a form of spread spectrum, which simpl…y means that data is sent in smallpieces over a number of the discrete frequencies available for use at any time in thespecified range. In CDMA, each phone's data has a unique code. All of the users transmit in the same wide-band chunk of spectrum.Each user's signal is spread over the entire bandwidth by a unique spreading code. At thereceiver, that same unique code is used to recover the signal. Because CDMA systemsneed to put an accurate time-stamp on each piece of a signal, it references theGPS system for this information. Between eight and 10 separate calls can be carried inthe same channel space as one analog AMPS call. ( Full Answer )
It will be the question in mind until service will roll out, but still some article released in news after Hariyana rollout, we can say it is possible.
As of right now ONLY AT&T carries the iPhone, they are on Edge coverage. BUT as you have probably heard, Verizon will be releasing the iPhone4 this February 2011. They are on a cdma network, as well as Sprint. It IS a possibility that Sprint could want in on the iPhone obsession, but lately Sprint h…as been looking into more Windows based phones. So it's unlikely that iPhone will be released by them, at least not anytime in the near future. It may be possible to jailbreak one to Sprint after the Verizon release but that's the only real possibility. ( Full Answer )
Both these techniques allow multiple transmitters to transmit simultaneously over a single communication channel. In FDMA, available bandwidth is divided into different frequency ranges and each transmitter is assigned a specific frequency range. In CDMA, a special signal called carrier is used to e…ncode the data signal. In this case, each transmitter uses a distinguished carrier signal to form the resultant signal. ( Full Answer )
The pilot channel corresponds to the all zeros Walsh code (Walsh channel 0), and contains the unmodulated quadrature PN spreading code. It is transmitted at higher power than the user channels, and is provided so that each subscriber within the cell can determine and react to the channel chara…cteristics while employing coherent detection ( Full Answer )
no we can't use ordinary sim card in cdma mobile they locking thier device with technology
You cant, GSM and CDMA are different technologies, GSM uses a sim card and CDMA does not.
It's a matter of convenience and practicality throughout the world more than anything else. GSM uses a SIM, Subscriber Identity Module, that connects the phone to a GSM network. This SIM is removable and replaceable. This allows the cellphone user to unlock a phone for a specific carrier or country …and use a compatible SIM for the unlocked network. In real world terms this means you can get your GSM phone unlocked for Mexico for example, and when you go there take out your current country SIM and put in a SIM from a local Mexican GSM provider and your phone will work without the special software and rates that CDMA requires. This is also useful if you want a particular phone on another GSM network locally such as wanting an iPhone for T-mobile service. You can buy an ATT iPhone which is GSM technology, and have it unlocked for use with T-mobile networks. Mind you this doesn't always translate to full functionality such as 3G may perform at 2G and the like depending on the compatibility of the phone and network. ( Full Answer )
Qualcomm, Boost Mobile, MetroPCS, Leap Wireless International Inc., Net 10, Sprint, Verizon, Cricket, and Alltel use CDMA technology.
How do you i unlock my mts zte c s1602 cdma mobile? Read more: http://wiki.answers.com/Q/How_do_you_i_unlock_my_mts_zte_c_s1602_cdma_mobile#ixzz2RhVPAd4u
The difference between CDMA mobile phones compared to other phones are that CDMA mobile phones do not require a SIM card. As well as this the carrier's information is stored in the phone's software.
You can find information on CDMA mobile phones online at the Wikipedia. Once on the website, type "CDMA" into the search field at the top of the page and press enter to bring up the information.
A CDMA cell phone does many things. A CDMA cell phone, which stands for Code Division Multiple Access, can make an unlimited number of calls because there is no limit.
CDMA Moblie Phones can be purchased at Home Shop 18. They may also be purchased at Boost Mobile, Shop Clues and Maniac Store as well as Newegg and Radio Shack.