Spatial Coupling vs. Block Coding: A Comparison

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Describes spatially coupled LDPC constructed from protographs by edge spreading (example m=2) and lifted with permutation matrices, showing threshold saturation where BP thresholds track MAP (rate-1/2 BEC threshold ≈0.488 vs Shannon 0.5). Wavefront propagation from low-degree checks gives wave-like decoding, but practical approach to MAP needs large section length (tens of thousands per section). Uses a sliding-window decoder to cut latency; simulations show a few‑tenths dB gain and latency reductions of 2–3× versus block LDPC at similar complexity.

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" chapters (16)

1. 0:00Intro
2. 1:26LDPC Block Codes
3. 2:06Code Ensembles - Minimum Distance
4. 3:16Thresholds of (J.K)-regular LDPC Block Code Ensembles
5. 4:08Protograph Representation
6. 9:43Terminated Spatially Coupled Codes
7. 12:10Wave-like Decoding of Terminated
8. 13:57Thresholds of Terminated
9. 17:20Threshold Saturation (BEC)
10. 20:13Distance Measures for SC-LDPC Codes
11. 21:23Decoding SC-LDPC Codes
12. 22:11Window Decoding Performance
13. 23:26Finite-Length Scaling for SC-LDPC Codes
14. 24:16Equal Latency Comparison for (3,6)-Regular LDPC Codes
15. 25:44Complexity Tradeoffs
16. 28:43Regular SC-LDPC Codes vs. Irregular LDPC-BCs