Throughput-Based Design for Polar-Coded Modulation

Abstract

Typically, forward error correction (FEC) codes are designed based on the minimization of the error rate for a given code rate. However, for applications that incorporate hybrid automatic repeat request (HARQ) protocol and adaptive modulation and coding, the throughput is a more important performance metric than the error rate. Polar codes, a new class of FEC codes with simple rate matching, can be optimized efficiently for maximization of the throughput. In this paper, we aim to design HARQ schemes using multilevel polar codedmodulation (MLPCM). Thus, we first develop a method to determine a set-partitioning based bit-to-symbol mapping for high order QAM constellations. We simplify the LLR estimation of set-partitioned QAM constellations for a multistage decoder, and we introduce a set of algorithms to design throughputmaximizing MLPCM for the successive cancellation decoding (SCD). These codes are specifically useful for non-combining (NC) and Chase-combining (CC) HARQ protocols. Furthermore, since optimized codes for SCD are not optimal for SC list decoders (SCLD), we propose a rate matching algorithm to find the best rate for SCLD while using the polar codes optimized for SCD. The resulting codes provide throughput close to the capacity with low decoding complexity when used with NC or CC HARQ.

Design and analysis of polar coded cooperation with incremental redundancy for IoT in fading channels

“…When the channel quality is improved, the used rate of user should be increased for higher efficiency. Based on the evaluated throughput, efficient search algorithms, such as golden‐section searching method [16], is employed to determine the optimal rates. With the known channel state estimation, adaptive CC of polar code is realized.…”

Energy Optimization For Hybrid ARQ With Turbo Coding: Rate Adaptation and Allocation

“…For simplicity, we let the maximum number of transmissions K be 2 in this section. It can be extended to arbitrary K. Note that in some literature [8], [9], [17], [25] the goal is to maximize the throughput. As shown in [8], the throughput of an HARQ system can be written as…”

“…The authors in [24] showed that correlated channels may yield higher throughput than independent channels for HARQ. HARQ code design for polar codes was studied in [25], and HARQ code design for low-density parity-check codes was studied in [26]. In [27], the authors surveyed HARQ code design for turbo codes.…”

CRC-Aided Parity-Check Polar Coding

“…When using HARQ or adaptive SCLD technique, throughput is an improtant metric to design coding scheme, where throughput of a decoder can be defined as [23] η = R(1 − P fer ) (15) where P fer is the FER of the decoder. In Fig.…”