MOD 8 UNIT 3A

What is Multiple Access in satellite communication?

The ability of satellites to multiplex signals from numerous terminals in various ways.

What does Frequency Division Multiple Access (FDMA) entail?

The first access method, which separates terminals by frequency within allocated bandwidth, using guard bands to minimize crosstalk (25MHz)

Advantageous to support connection oriented applications

Inefficient for satellites total capacity due to users not constantly utilizing their frequency

What is a key advantage of FDMA?

It supports connection-oriented applications.

What is the efficiency issue with FDMA?

It is inefficient for satellite's total capacity because users do not constantly utilize their frequency.

What is Time Division Multiple Access (TDMA)?

A method that assigns terminals dedicated time slots on a channel's bandwidth to prevent interference.

What is required to employ TDMA effectively?

Stringent timing and network controls.

How does Code Division Multiple Access (CDMA) work?

It uses pseudorandom noise codes to separate users, allowing all terminals to transmit at the same time over the same frequency.

Receiving terminal actively looks for specific coded waveform

200 KHz

What does Wideband Code Division Multiple Access (WCDMA) improve upon?

It uses wider frequency bands than CDMA for higher throughput for data transmission.

What is a characteristic of WCDMA?

It uses a 5MHz wide carrier and operates in a coded spread spectrum mode.

What does Demand Assigned Multiple Access (DAMA) provide?

A first come first serve basis for frequency allocation, returned to a pool after use.