LDPCTurboPolarCodes

LDPCTurboPolarCodes are a class of error-correcting codes that integrate principles from low-density parity-check (LDPC) coding, polar coding, and turbo decoding concepts. The goal is to combine the strong finite-length performance of polar codes with the flexible rate and decoding characteristics of LDPC-like structures, using an iterative, turbo-inspired framework.

Construction and encoding approaches for LDPCTurboPolarCodes typically involve a hybrid structure in which information bits are processed through both polar and LDPC-oriented components. One common design idea is to partition the information sequence into parts that are handled by a polar code and by an LDPC-like parity-check layer, followed by a coordinated encoding step that connects the two components. The overall codeword thus reflects both polarization-based reliability ordering and LDPC-style parity constraints, enabling more flexible rate matching and potentially better short-to-medium length performance.

Decoding of LDPCTurboPolarCodes relies on iterative message passing between a polar-based decoder and an LDPC BP (belief propagation) decoder. The polar decoder (which can be successive cancellation, successive cancellation list, or a polar BP variant) provides soft information that is exchanged with the LDPC decoder during turbo-like iterations. Through successive refinements, the joint decoder aims to improve bit- and block-error rates, particularly at moderate block lengths and certain channel conditions.

Performance and considerations: LDPCTurboPolarCodes can offer gains over standalone polar or LDPC schemes in targeted regimes, at the cost of higher decoding complexity and latency due to the iterations. Design choices such as polarity ordering, parity-check structure, and iteration schedule are important to achieve robust convergence. The concept is primarily of research interest, with ongoing work exploring practical configurations for high-throughput communication systems.