Youtube Link: https://youtu.be/7IVTclUJLTM

1. Overview of Adaptive Modulation & CodingTechnique
(AMC)
Presented By
NAME: SUMAN BHATTACHARYYA
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2. Table of Content
 Introduction
 Adaptive modulation & Coding
 Block Diagram
 Importance of AMC
 Constraints
 Goal
 Current system using AMC
 Advantages of AMC
 Challenges of AMC
 Conclusion
 References
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3. Introduction
 Adaptive modulation and coding enables robust
and spectrally efficient transmission over time-
varying channels.
 AMC was introduced in the late sixties and early
seventies.
 The basic idea behind it is to adopting
transmission parameters according to channel
conditions by monitoring and measuring them.
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4. Adaptive modulation and coding (AMC)
 The modulation process formats the signal to best
transmit bits
◦ To overcome noise.
◦ To transmit as many bits as possible.
 Coding detects and corrects errors.
 AMC adapts to channel conditions
◦ Measures channel conditions.
◦ Sends messages between transmitter and
receiver to coordinate changes.
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5. Adaptive modulation and coding block
diagram
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6. Why Adaptive Modulation And Coding Is
Important ?
 Without AMC, there is inefficient utilization of
channel and wastage of power.
 With AMC, data rate and signal power are varied
as per the channel conditions for efficient
utilization of resources.
 AMC guarantees 99% of data transfer even at
worst channel conditions without any wastage of
resources.
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7. Constraints
 Adaptive modulation requires a feedback path
between the transmitter and the receiver, which
may not be feasible for some systems.
 If the channel changes faster than it can be
estimated and fed back to the transmitter,
adaptive modulation will perform very poorly.
 How often the transmitter can change its rate and
power.
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8. Goal Of Adaptive modulation and coding
 Adaptive Modulation & Coding is used to
improve the operational efficiency of Microwave
links by increasing network capacity over the
existing infrastructure.
 Adaptive Modulation means dynamically varying
the modulation in an errorless manner in order to
maximize the throughput under momentary
propagation conditions.
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9. CURRENT SYSTEMS USING AMC
 EGPRS for data transmission in GSM cellular
system uses 8PSK with 5 different code rates and
GMSK with 4 different code rates. Total 9
different coding and modulation schemes.
 GPRS for data transmission in IS-136 TDMA
cellular systems can use 4, 8, and 16 level PSK
modulation.
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10. Advantages Of Adaptive Modulation And
Coding
 Adaptive Modulation & Coding allows a wireless
system to choose the highest order modulation
depending on the channel conditions.
 Adaptive Modulation & Coding allows the system
to overcome fading and other interference.
 Maximize the throughput.
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11. Challenges
 AMC is sensitive to measurement error and delay.
In order to select the appropriate modulation, the
scheduler must be aware of the channel quality.
 Errors in the channel estimate will cause the
control to select the wrong data rate and either
transmit at too high a power, wasting system
capacity, or too low a power, raising the block
error rate.
 Complexity is very High.
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12. Conclusion
 Adaptive modulation is one method to improve
the throughput and/or range.
 The use of adaptive modulation allows wireless
technologies to optimize throughput, yielding
higher throughputs while also covering long
distances.
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13. References
 Wireless Communications by Andrea Goldsmith
(Edition 2005)
 https://iopscience.iop.org/article/10.1088/1757-
899X/78/1/012016#:~:text=Adaptive%20Modulation%2
0and%20Coding%20(AMC,MIMO%20antenna%20con
figuration%20is%20studied.
 https://www.academia.edu/36992931/Implementation_w
ith_Adaptive_Modulation_Technique_and_OFDM_Base
d_Approach
 https://uweb.engr.arizona.edu/~ivan/JOCN_AMC_FSO_
MAy10.pdf
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14. Thank You….
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