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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
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What is near-far effect?
Adjacent channel interference nearby frequency leak into passband. The problem can be worse if an adjacent channel user is transmitting in very close range to a subscriber receiver. This problem is referred as near far affect. By Kazi Ashique Ahmed Rafi it usaully occurs in CDMA when users are transmitting unequal powers. by salman ahmed
What is near effect?
Adjacent channel interference nearby frequency leak into passband. The problem can be worse if an adjacent channel user is transmitting in very close range to a subscriber receiver. This problem is referred as near far affect. By Kazi Ashique Ahmed Rafi it usaully occurs in CDMA when users are transmitting unequal powers. by salman ahmed
Why near-far effect is there in CDMA and not in gsm?
The development of the ability to control the transmission power of the mobiles led to the re-evaluation of a spread spectrum technique invented in World War II, known as CDMA (Code Division Multiple Access). This technique permitted many more users to utilise the same system, but up until then had not been workable in the mobile environment due to a phenomenon known as near-far effect. Initially its use was confined to small aperture satellite services, and also, due to its security virtues, to military applications, where it was used to avoid jamming and detection of sensitive transmissions. The restricted use was due to the inability to eliminate narrowband interference caused by louder signals with greater amplitude drowning out lower power signals. This prevented correct demodulation of the wanted signal. The propagation path loss difference between those located close to the base station and those in fringe areas can be many tens of dB without regulation! (This is not the case in satellite systems where signal levels do not vary greatly.) Through control of the transmission power of the mobiles it became possible to ensure all accessing signals could be received at similar amplitude, thus eliminating near-far effect and enabling the same frequency spectrum to be reused in all the cells. The use of amplifier boosters that are not compatible with CDMA power regulation, therefore, prevents the elimination of near-far effect. This makes it impossible for the system to operate correctly, undermining the foundations of the basic concept of successful CDMA operation.
Why FDMA is not sensitive to near- far problems?
A frequency-division multiple access system (FDMA) is much less sensitive to near-far problems than code-division multiple access systems (CDMA). A FDMA receiver must select signals from a desired transmitter tuned to one frequency, and block signals from transmitters tuned to other frequencies -- this is fairly easy and low-cost to do with standard bandpass filters, even when the near-far problem causes undesired transmitters to sound much louder than the desired transmitter, as long as adequate "guard bands" separate one transmitter from the next. A DSS CDMA receiver must select signals from a desired transmitter and block signals from other transmitters, even when they are all transmitting on the same frequencies at the same time -- this cannot be done with standard bandpass filters. The techniques DSS CDMA receivers use to select the desired signals are much more sensitive to near-far problems.
Which is best CDMA or gsm?
CDMA, offers better data transfer
Are HTC phones CDMA?
Not all HTC phones are powered by CDMA.Some of CDMA phones are :HTC S720 (CDMA)HTC P4000 (CDMA)
Which one is better GSM or CDMA mobile?
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 bandwith 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.
Is ATT CDMA?
no its HSDPA sprint or Verizon or both are cdma
What if operating frequency for CDMA network in yemen?
cdma gsm
What is CDMA repeater?
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/wiki/CDMA
Can you convert cdma sim to cdma?
Code division multiple access
Is CDMA better or gsm to be used in egypt?
does cdma work in egypt
