A more recent technique is time division multiple access tdma. Fundamentals of communications access technologies. First generation of cellular systems was implemented in the late sixties till the late eighties with analog systems using frequency division multiple access fdma. Pdf the capacity of mobile protocols such as fdma frequency division multiple access, tdma time division multiple access, and cdma. For browsing the web, to watch videos and to download music, cdma is better choice as compared to gsm. This technique may be viewed as a combination of fdm and. Only in combination with tdma, fdma or cdma useful. The adobe flash plugin is needed to view this content. Fdma, time division multiple access tdma, code division.
Pdf today, frequency spectrum has become a scarce network resource in wireless communications. Still faces some problems, higher complexity, lowered expectations, will be integrated with tdma or fdma. Multiple access technique lecture 8 website staff ui. Multiple access capability is also provided by code division multiple access cdma. Electrical engineering department university of indonesia. Tdma time division multiple access and cdma code division multiple access. Many of the problems experienced in tdma due to different propagation delays are eliminated in fdma. Fdma, time division multiple access tdma and code division multiple access cdma techniques 1.
The number of channels that can be simultaneously supported in a fdma system is. Project 25 tdma standard the tia102 suite of standards defines project 25 p25 tdma, adding spectrumefficient tdma voice service to the existing p25 fdma trunked voice and packet data services. View tdma, cdma, fdma ppts online, safely and virusfree. When allslices are occupied in the system no additional wireless terminal can be accommodated. The capacity of mobile protocols such as fdma frequency division multiple access, tdma time division multiple access, and cdma code division multiple access systems are compared assuming. Time division cdma, time division frequency hopping, fdmacdma, etc. Gsm uses a combination of both tdma and fdma techniques. Standards in fixed networks, together with fdma or sdma used in many mobile networks. Gsm uses both time division multiple access tdma and frequency division multiple access fdma for user and ell separation. Ppt cdma fdma tdma powerpoint presentation free to download id.
So cdma is known to cover more area with fewer towers. P25 tdma capable systems use the p25 fdma control channel for all call requests, which allows systems to support fdma calls as well as tdma calls. The major disadvantage of fdma is the relatively expensive and complicated bandpass filters required. Cdma system separates users through the assignment of different. Comparison between cdma and tdma air interface for. Bothtechniques assign particular frequency or time slices to di.
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