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Channel Coding (Proakis: chapter 12.4, 12.5, 12.6, 13.1, 13.2) Dong In Kim College of Info/Comm Engineering Sungkyunkwan University

Channel Coding - SKKU

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Channel Coding(Proakis: chapter 12.4, 12.5, 12.6, 13.1, 13.2)

Dong In KimCollege of Info/Comm Engineering

Sungkyunkwan University

Digital Communication System

Channel Capacity

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We can achieve 1 bit/sec/Hz spectral efficiency with SNR=0dB in channel capacity while in BPSK with SNR=9.6dB at BER=10**-5.

Channel Coding

Types of Channel Coding

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Memoryless channel coding
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Channel coding with memory

Classes of Block Codes

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Non-binary block codes
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Non-binary block codes

Block Codes

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Example : (7,4) Hamming Code

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Properties of Block Codes

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This cyclic property is useful for simplifying the decoding procedure via a shift register.

Hamming Distance

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Decoding of Block Codes

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One-bit error is more likely whereas two-bit error is less likely!

Error Correction Capability

Probability of Codeword Error

Example : (7,4) Hamming Code

Per-bit SNR for Coded System

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Example : BPSK

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BER for Coded System ?