4. What is a multiplexer…..(MUX)..?
Definition
Multiplexer is a digital switch that has multiple inputs
(sources) and a single output(destination).
The selected lines determine which
input is connected to the output.
10. Difference between TDM & FDM
TDM
TDM total available time is divided
into several users.
Transmission of two or more signal
on the same path, but at different
times.
Use in digital system.
FDM
Total frequency bands are divided
into several users.
A multiplex system for
transmitting two or more signals
over a common path.
Use in analog system.
11. Synchronous means that, change in logic levels is
simultaneous if some change occurs it is of some regular
pattern, there is a clock signal which control this regular
variation.
In asynchronous there is no such clock signal.
12. Sharing a Media: Multiplexing
Multiplexing means combining different communication
streams into just one communication line.
Example 1: Frequency-Division Multiplexing. Used by radio,
TV and cable TV. Different stations transmit over different
“channels” (with different frequency).
Example 2:Time-Division Multiplexing. For use with digital
signals. Used for the communication between telephone
switching offices.
13. Telephone network
base transceiver station (BTS)
In the telephone network, multiplexing and switching
techniques.
Multiple telephone channels may share a
transmission link by means of multiplexing.
FDM (Frequency Division Multiplexing) is used in
analogue systems (a telephone analogue channel has
a nominal bandwidth of 4 kHz).
14. Application of multiplexer
The multiplexer is most commonly used in phone
networks. In the past, people used to "wait for a phone
line to become available" when they wanted to call a
certain number. The truth is that phone grids had
limited capacity in the past. Thus the wait (for a phone
line to clear).
As you probably know, the multiplexer basically groups
signals together in order to be carried more efficiently.
A famous application of multiplexing is DSL.
15. STDM (Synchronous Time Division Multiplexing) is used in
digital systems (the basic telephone digital channel has a
capacity of 64 kbit/s).
The telephone network adopts the Circuit Switching
technique.
Data networks may use circuits to build their own
infrastructure based on a different techniques (Packet
Switching).
