LDPC and Polar Codes in 6G: A Comparative Study and Unified Frameworks

Relevance. As sixth-generation (6G) wireless systems pursue extreme requirements in throughput, latency, reliability, and adaptability, the design of channel coding schemes becomes increasingly critical. This paper presents a comprehensive comparison between Low-Density Parity-Check (LDPC) codes and Polar codes, the two most promising channel coding candidates for 6G. We analyze their respective strengths across key metrics including data throughput, error-correction capability, decoding complexity, hardware implementation, and adaptability to dynamic communication scenarios. Furthermore, we explore recent advances in unified channel coding frameworks, including generalized LDPC with Polar-like components (GLDPC-PC) and artificial intelligence (AI)-assisted decoders, which aim to bridge the performance gap across diverse 6G scenarios.

Purpose. This paper aims to provide a systematic and measurable comparison of LDPC and Polar codes for 6G, while also examining the feasibility of unified coding frameworks to bridge their performance gaps.

Methods used. This study employs a systematic literature review. The analysis first evaluates LDPC and Polar codes against four key metrics: data throughput, error-correction capability, decoding complexity and hardware implementation, and flexibility. It then examines advancements in long- and short-block code design and unified frameworks. The comparison is substantiated by a quantitative analysis of documented performance data.

Results. LDPC codes demonstrate strong hardware scalability and parallelism, while Polar codes excel in short-packet error correction. Unified approaches integrate their advantages, enhancing adaptability to diverse scenarios.

Novelty. Unlike prior works with fragmented analyses, this study combines comparative evaluation with an exploration of unified frameworks, providing an integrated perspective.

Theoretical significance. The results enrich theoretical understanding of 6G coding trade-offs. The paper offers a guidance for researchers and standardization bodies in designing future coding strategies.

Practical significance. The practical significance of the work lies in the fact that the conducted comparative study of LDPC and Polar codes enables a well-founded selection of channel coding schemes for various 6G communication scenarios. The obtained results can be used in the design of 6G communication systems to optimize the choice between codes: Polar codes are suitable for short packets requiring low latency and high energy efficiency, while LDPC codes (particularly SC-LDPC) are ideal for long codes where hardware scalability and parallelism are critical. The results are also applicable to the development of unified decoders and adaptive systems capable of dynamically switching between schemes, which enhances the flexibility and efficiency of future telecommunication infrastructures.

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