MULTIPLE ACCESS TECHNOLOGY
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INTRODUCTION


Advancement in communication and information processing technologies creates more new applications and products.
The demand for wireless and satellite communication devices has increased rapidly and the trend is expected to continue.
Whenever multiple carriers are utilized in satellite communications, it is necessary that a multiple accessing format be established over the system.

MULTIPLE ACCESS TECHNOLOGY

Whenever multiple carriers are utilized in a satellite communications, it is necessary that a multiple access technology be established over the system.
3 basic multiple access technology
Frequency division multiple access (FDMA).
Time division multiple access (TDMA).
Code division multiple access. (CDMA).



ADVANTAGES OF FDMA :
Reducing the information bit rate and using efficient digital codes can increase the capacity.
Hardly any equalization required.
Technological advances required for implementation are simple.

DISADVANTAGES OF FDMA :
Doesn’t differ significantly from analog systems; capacity improvement depends on reducing signal to noise ratio (SNR).
Maximum bit rate per channel is fixed and small.