This is a template to create an Instructional Design Document of the concept you have selected for creating animation.

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Welcome
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• This is a template to create an Instructional
  Design Document of the concept you have selected
  for creating animation.
• This will take you through a 5 section process to
  provide the necessary details to the animator
  before starting the animation.
• The legend on the left will indicate the current
  status of the document. The Black coloured number
  will denote the current section, the Turquoise
  color would denote the completed sections, and
  the Sky blue color would denote the remaining
  sections.
• The slides having 'Instructions' would have a
  Yellow box, as shown on the top of this slide.

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Repetition CodeThe simplest error correcting code
Binary Symmetric Channel
Prof. Saravanan Vijayakumaran
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Definitions and Keywords
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Bit A binary digit which can take the value 1
or 0. Channel The medium through which
information transfer takes place. Noisy Channel
A channel which may modify the information
which is transmitted through it. Binary channel
A channel which takes bits as input and
produces bits as output. Error An error is
said to have occurred if the received information
does not match the transmitted information.
Errors are caused by noise in the channel. Bit
Error If the channel changes a bit which is
transmitted over it, a bit error is said to have
occurred.
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Definitions and Keywords
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Single Bit Error Suppose a string of bits is
transmitted through a noisy channel. A single bit
error is said to have occurred if the channel
changes only one of the bits, i.e. the
transmitted bit string and the received bit
string differ only in one bit. Double Bit Error
- Suppose a string of bits is transmitted through
a noisy channel. A double bit error is said to
have occurred if the channel changes only two of
the bits, i.e. the transmitted bit string and the
received bit string differ only in one
bit. Binary Symmetric Channel (BSC) A common
channel model used in coding theory and
information theory to represent a noisy channel.
The inputs and outputs to the BSC are the bits 1
and 0. An input bit arrives without change at the
output or is flipped with some probability.
Crossover Probability The probability with
which a bit at the input of the BSC is flipped.
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Concept details
INSTRUCTIONS SLIDE
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• In this section, provide the stepwise detailed
  explanation of the concept.
• Please fill in the steps of the explanation of
  the concepts in the table format available in the
  slides to follow (see the sample below).
• Resize the table dimensions as per your
  requirements.

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Concept details
INSTRUCTIONS SLIDE
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• In this animation, we want to show the operation
  of the repetition code for two types of channels
• A channel which introduces a fixed number of
  errors. Although the channel introduces a fixed
  number of errors, position of the errors is not
  fixed. For example a channel which changes only
  one bit in the transmitted bit string. So if
  111000 is the information transmitted, the
  received bit string may be 101000 or 111100
  or....
• The binary symmetric channel

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Concept details Step 1
INSTRUCTIONS SLIDE
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• The user can select between the fixed error
  channel and the binary symmetric channel. Once he
  selects the type of channel, there will be five
  information bits 10101
• Each bit will be repeated three times as it
  passes through the block titled Repetition
  Encoder. Make sure the three repetitions of each
  bit appear together and there is a delay between
  the repetitions of different bits

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Concept details Step 2
INSTRUCTIONS SLIDE
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• The repeated bits are passed through a block
  titled Noisy Channel. The type of channel (single
  error, double error, binary symmetric channel) is
  chosen by the user. The errors are shown in red.

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Concept details Step 3
INSTRUCTIONS SLIDE
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• The bits which have passed through the channel
  are decoded by a block called the Majority Vote
  Decoder(MVD). The MVD takes three bits as input
  and outputs the majority of the three bits as the
  output.

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Interactivity and Boundary limits
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Number of repetitions can be from 2 to 7.
Larger values cannot be accommodated in the
screen.
The user can change the number of times a bit is
repeated. For eg, she can choose 5 instead of 3.
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The number of errors a noisy channel introduces
can be changed by the user. This applies only to
the channel which introduces a fixed number of
errors. For eg, the number of errors introduced
by the channel can be 2 instead of 1 as shown
in the figure above.
Number of errors can be from 1 to 10.
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The crossover probability can be from 0 to 0.5.
If the channel type chosen by the user is the
binary symmetric channel, the user can change the
crossover probability.
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Links for further reading
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1 Elements of Information Theory, by Thomas
Cover and Joy Thomas 2 Repetition Code on
Wikipedia http//en.wikipedia.org/wiki/Repet
ition_code 3 Majority Logic Decoding on
Wikipedia http//en.wikipedia.org/wiki/Major
ity_logic_decoding
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• Thank you