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