Presentation is loading. Please wait.

Presentation is loading. Please wait.

Coding Theory Efficient and Reliable Transfer of Information

Similar presentations


Presentation on theme: "Coding Theory Efficient and Reliable Transfer of Information"— Presentation transcript:

1 Coding Theory Efficient and Reliable Transfer of Information
Information Theory Algebraic Coding Theory

2 Information Source Encoder Communication Channel Decoder Information Sink Noise

3 What is Information

4 Information Theory Information is a decrease in uncertainty
What is uncertainty?

5 Uncertainty Number of Possibilities 2 ways 3 ways Together: 6 ways
Prefer additive measure take logarithm of number of symbols M

6 Symbols with unequal probability

7 Average uncertainty per symbol: Shannon Entropy

8

9 Mutual Information Change in uncertainty
Change in uncertainty in one random variable from knowledge of another

10 Molecular Information Theory
Applied to DNA Sequences Pattern of information, or label, to ribosome to start translation at given site

11 Channel Capacity Maximum rate at which information can be sent and recovered with vanishing probability of error Channel Coding Theorem

12 Source Coding Can’t Compress information below entropy
Optimal Prefix-Free Codes for Representation Code Lengths are greater than or equal to entropy of source

13 Rate Distortion Encoding bits of information per symbol bit
How many given a certain distortion (error) p 1 1-p

14 Algorithmic Information Theory
Kolmogorov Descriptive complexity of an object is the length of the shortest computer program that describes the object If equal to length of object then it is random Pi


Download ppt "Coding Theory Efficient and Reliable Transfer of Information"

Similar presentations


Ads by Google