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which is better---cdma or fdma?

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cdma( Code Division Multiple Access) is better than fdma( Frequency Division Multiple Access).Frequency Division Multiple Access (FDMA), different signals are assigned frequency channels. A channel is a frequency. FDMA is a basic technology in the analog Advanced Mobile Phone System (AMPS). With FDMA, each channel can be assigned to only one user at a time. In Code Division Multiple Access (CDMA), each user is assigned a different pseudorandom binary sequence that modulates the carrier, spreading the spectrum of the waveform and giving each user a unique code pattern. This technology is used in ultra-high-frequency (UHF) cellular telephone systems in the 800-MHz and 1.9-GHz bands.
Posted: 30-10-2011 @ 14:29:40
As one of the major problems facing the development of telecommunications, bandwidth demand has driven the search for protocols that could be used to maximize bandwidth efficiency. Multiple accesses ("multiplexing" for short) enable multiple signals to occupy a single communications channel. There are three basic types of division-based protocols used to do this: frequency division multiple access (FDMA), time division multiple access (TDMA) and code division multiple access (CDMA). With Frequency Division Multiple Access (FDMA), different signals are assigned frequency channels. A channel is a frequency. FDMA is a basic technology in the analog Advanced Mobile Phone System (AMPS). With FDMA, each channel can be assigned to only one user at a time. FDMA is also used in the Total Access Communication System (TACS).
Posted: 25-08-2011 @ 16:51:30
cdma
Posted: 18-08-2011 @ 14:59:02
cdma
Posted: 03-08-2011 @ 18:35:27
cdma
Posted: 02-08-2011 @ 22:55:33
cdma
Posted: 02-08-2011 @ 18:12:35
fdma (frequency division multiple access) is better than cdma (code division multiple access)
Posted: 02-08-2011 @ 14:49:29
Frequency division multiple access, which is the acronym of FDMA came. In this the given bandwidth is dived into fixed number of frequencies horizontally. And in this also the one frequency is assigned to individual users; it will remain idle, if that user is not sending any data. In this also there is bandwidth and time wastage. Here also data stolen problem Then after that a new technology came Code Division Multiple Access that is the acronym of CDMA. This is the 3G technology. In this bandwidth is not divided into any thing. Data can be send to any frequency at any time by any user; there is not any fixed number of users. And the data steel problem is also solved. This technology is in use now a day. The new updating of the CDMA is WCDMA. In this all the good qualities of the TDMA, FDMA, and CDMA is used.
Posted: 02-08-2011 @ 08:35:57
FDMA is basically Analog technology and the oldst one CDMA is newest of all, whre all users are allocated a distinct code. so cdma is best one
Posted: 01-08-2011 @ 23:50:07
FDMA is basically Analog technology and the oldst one CDMA is newest of all, whre all users are allocated a distinct code. so cdma is best one
Posted: 01-08-2011 @ 23:47:58
CDMA is the 3G technology. In this bandwidth is not divided into any thing. Data can be send to any frequency at any time by any user.While in FDMA, the given bandwidth is dived into fixed number of frequencies horizontalli.And it this also the frequency is assigned to individual users. So, you can see CDMA is much better than FDMA.
Posted: 01-08-2011 @ 23:33:48
cdma
Posted: 01-08-2011 @ 22:19:59
cdma is much better than fdma
Posted: 01-08-2011 @ 22:17:34
FDMA,as the name implies operates by dividing thebandwidth of the wireless channel equally among a number of users wanting to access the channel.ie frequency division multiple access. It was the first technology used. TDMA was the next to come, it was the opening of digital world.It had an attractive feature that it does accommodate the transmission of source channel encoded digital data alongside digitized speech in straightforward manner.With TDMA channel bandwidths are wider than FDMA and fading is no longer frequency flat,but rather frequency selective.IT is time division multiple access.GSM was from this global system for mobile,it has frame structure with 8 time slots. CDMA refers to a multiple-access technique in which the individual terminals use spread spectrum technique and occupy all the spectrum whenever they transmit,it is the interference attenuation property of the spread-spectrum that allows multiple users to occupy the same spectrum at the same time.It is the coded division multiple access it uses the coding. The 3g is from this, WCDMA is wide band cdma, that is it uses both fdma and tdma techniques very effectively to bring about a big change in mainly the packet radio systems Cdma is Better.
Posted: 01-08-2011 @ 21:58:34
cdma is better than fdma .Because cdma is good at the following:: Methods of multiplexing signals Time division Frequency devision Carrier Detect Multiple Access
Posted: 01-08-2011 @ 17:37:04
cdma( Code Division Multiple Access) is better than fdma( Frequency Division Multiple Access).Frequency Division Multiple Access (FDMA), different signals are assigned frequency channels. A channel is a frequency. FDMA is a basic technology in the analog Advanced Mobile Phone System (AMPS). With FDMA, each channel can be assigned to only one user at a time. In Code Division Multiple Access (CDMA), each user is assigned a different pseudorandom binary sequence that modulates the carrier, spreading the spectrum of the waveform and giving each user a unique code pattern. This technology is used in ultra-high-frequency (UHF) cellular telephone systems in the 800-MHz and 1.9-GHz bands.
Posted: 01-08-2011 @ 17:33:26
CDMA is better CDMA Same frequency is used by every user and simultaneous transmission occurs Every narrowband signal is multiplied by wideband spreading signal, usually known as codeword Every user has a separate pseudo-codeword, i.e., orthogonal to others Only the desired codeword is detected by the receivers and others appear as noise It is mandatory for the receivers to know about the transmitter’s codeword FDMA When the channel is not in use, it sits simply idle Bandwidth of Channel is relatively narrow (30 KHz), known as narrowband system Little or no equalization is needed for spreading symbol time Analog links are suitable for FDMA Framing or synchronization bits are not needed for continuous transmission Tight filtering is needed to minimize interference Combined with FDD for duplexing
Posted: 01-08-2011 @ 17:20:16