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Threshold Computation for Spatially Coupled Turbo-Like Codes on the AWGN Channel
Muhammad Umar Farooq1, Alexandre Graell I Amat2, Michael Lentmaier1
1Department of Electrical and Information Technology, Lund University, 22100 Lund, Sweden.
Entropy (Basel, Switzerland)
|March 6, 2021
Summary
This study analyzes spatially coupled turbo-like codes (SC-TCs) on AWGN channels. We show that binary erasure channel (BEC) thresholds efficiently predict belief propagation (BP) decoding thresholds, avoiding complex computations.
Area of Science:
- Information Theory
- Coding Theory
- Digital Communications
Background:
- Spatially coupled turbo-like codes (SC-TCs) offer near-capacity performance.
- Belief propagation (BP) decoding is crucial for analyzing code performance.
- Accurate threshold analysis is essential for designing efficient error correction codes.
Purpose of the Study:
- To perform a belief propagation (BP) decoding threshold analysis of spatially coupled (SC) turbo-like codes (TCs) (SC-TCs) on the additive white Gaussian noise (AWGN) channel.
- To investigate efficient methods for predicting BP thresholds of SC-TCs.
- To establish a relationship between BEC thresholds and AWGN channel BP thresholds for SC-TCs.
Main Methods:
- Review of Monte-Carlo density evolution (MC-DE) for BP threshold determination.
- Application of efficient prediction methods based on binary erasure channel (BEC) thresholds.
- Comparative analysis of MC-DE computed thresholds and predicted thresholds.
Main Results:
- Demonstrated efficient prediction of BP thresholds for SC-TCs over AWGN channels using BEC thresholds.
- Showcased that prediction methods significantly reduce computational complexity compared to MC-DE.
- Observed a strong correlation between MC-DE and predicted thresholds.
Conclusions:
- BP thresholds of SC-TCs over AWGN channels can be efficiently predicted from their BEC thresholds.
- The similarity in thresholds suggests a link to threshold saturation and capacity-approaching MAP performance.
- This prediction method offers a computationally advantageous alternative to MC-DE for SC-TC analysis.
Keywords:
AWGN channelcoding thresholdsconcatenated convolutional codesdensity evolutioniterative decodingspatially coupled codesturbo codesMore Related Videos
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