This document discusses multiplexing techniques used in mobile computing. It describes four types of multiplexing: frequency division multiplexing (FDM), time division multiplexing (TDM), code division multiplexing (CDM), and space division multiplexing (SDM). For each type, it provides details on how the technique works and its advantages and disadvantages. FDM uses different frequencies to transmit multiple signals simultaneously. TDM divides a signal into time slots to share a frequency. CDM assigns unique codes to signals sharing the same frequency. SDM splits a channel across physical locations.

1. Presented By:
Bhabanta Padhan
Branch: I.T
Jharsuguda Engineering School, Jharsuguda

2. Content:
 What is multiplexing ?
 Types of multiplexing in mobile computing
 Advantages
 Disadvantages
 Uses of multiplexing in mobile computing

3. What is multiplexing ?
 It is the set of techniques that allows the simultaneous
transmission of multiple signals across a single data link.
 Multiplexing is done using a device called Multiplexer (MUX)
that combine n input lines to generate one output line i.e. (many
to one).
 At the receiving end a device called Demultiplexer (DEMUX)
is used that separate signal into its component signals i.e. one
input and several outputs (one to many).

4. Types of Multiplexing
 Frequency Division Multiplexing (FDM)
 Time Division Multiplexing (TDM)
 Code Division Multiplexing (CDM)
 Space Division Multiplexing (SDM)

5. Frequency Division Multiplexing
 FDM is inherently an analog technology.
 It is a method of multiplexing by which multiple number of
information are in different frequency.
 FDM’s most common applications are traditional radio,
television broadcasting , mobile or satellite stations, cable
television

7. Advantages of FDM
1. The concept of frequency division multiplexing (FDM)
applies to both analog signals and digital signals.
2. It facilitates you to send multiple signals simultaneously
within a single connection.
Disadvantages of FDM
1. It is less flexible.
2. In FDM, the bandwidth wastage may be high.

8. Time Division Multiplexing
 It is a method in which the multiple number of information are
communicate with in a different slot of time.
 The Time frames of the same intervals are divided so that you
can access the entire frequency spectrum at that time frame.
 This method is used in telegraphy or in ISDN telephonic
services.

10. Advantages of TDM
1. It facilitates a single user at a time.
2. It is less complicated and has a more flexible architecture.
Disadvantages of TDM
1. It isn't easy to implement.

11. Code Division Multiplexing
 It is a method of multiplexing in which multiple number of
information are multiplex in different code .
 The Code Division Multiplexing or (CDM) allots a unique
code to every channel so that each of these channels can use
the same spectrum simultaneously at the same time.
 It is mainly used in Cell Phone Spectrum Technology (2G, 3G
etc.)

12. Advantages of CDM
1. It is highly efficient.
2. It faces fewer Inferences.
Disadvantages of CDM
1. The data transmission rate is low.
2. It is complex.

13. Space Division Multiplexing
 SDM is a method in which we split a communication channel
into multiple different physical location and allocated each stream
of data onto each of the location.
 It is a combination of FDM and TDM.
 It passes messages or data-parallel with the use of specific
frequency at a specific. It means a particular channel will be used
against a specific frequency band for some amount of time.
 It is used in GSM (Global Service for Mobile) Technology

14. Advantages of SDM
1. In SDM, the data transmission rate is high.
2. It uses Time and Frequency bands at its maximum potential.
Disadvantages of SDM
1. An inference may occur.
2. It faces high inference losses.

15. Thank You