channel coding - skku
TRANSCRIPT
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 ?