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A hardware architecture is presented to decode (N, K) polar codes based on a low‐density parity‐check code‐like decoding method. By applying suitable pruning techniques to the dense graph of the polar code, the decoder architectures are optimized using fewer check nodes (CN) and variable nodes (VN). Pipelining is introduced in the CN and VN architectures, reducing the critical path delay. Latency is reduced further by a fully parallelized, single‐stage architecture compared with the log N stages in the conventional belief propagation (BP) decoder. The designed decoder for short‐to‐intermediate code lengths was implemented using the Virtex‐7 field‐programmable gate array (FPGA). It achieved a throughput of 2.44 Gbps, which is four times and 1.4 times higher than those of the fast‐simplified successive cancellation and combinational decoders, respectively. The proposed decoder for the (1024, 512) polar code yielded a negligible bit error rate of 10−4 at 2.7 Eb/No (dB). It converged faster than the BP decoding scheme on a dense parity‐check matrix. Moreover, the proposed decoder is also implemented using the Xilinx ultra‐scale FPGA and verified with the fifth generation new radio physical downlink control channel specification. The superior error‐correcting performance and better hardware efficiency makes our decoder a suitable alternative to the successive cancellation list decoders used in 5G wireless communication. [ABSTRACT FROM AUTHOR]

Recently, polar code has attracted the attention of many scholars and has been developed as a code technology in coded‐cooperative communication. We propose a polar code scheme based on Plotkin structure and quasi‐uniform punching (PC‐QUP). Then we apply the PC‐QUP to coded‐cooperative scenario and built to a new coded‐cooperative scheme, which is called PCC‐QUP scheme. The coded‐cooperative scheme based on polar code is studied on the aspects of codeword construction and performance optimization. Further, we apply the proposed schemes to space–time block coding (STBC) to explore the performance of the scheme. Monte Carlo simulation results show that the proposed cooperative PCC‐QUP‐STBC scheme can obtain a lower bit error ratio (BER) than its corresponding noncooperative scheme. [ABSTRACT FROM AUTHOR]

Summary: A novel scheme for designing polar codes with specific decoding schemes in the additive white Gaussian noise channel is presented in this paper. The code construction strategy is built on the genetic algorithm (GA) where successive evolution of populations (or group of information sets) leads toward fittest candidate to attain finest error‐rates. In this work, it is shown that better error‐rates can be attained by both successive cancelation list decoding using GA with no cyclic redundancy check (CRC) and belief propagation decoding using GA with no CRC and no list, compared to existing polar decoding schemes. Our proposed polar code design scheme using GA has the ability to attain a target block error rates with the least possible SNR and using no additional CRC by exploiting least belief propagation iterations or lesser successive cancelation list list size with no self‐alterations in the decoding algorithm. [ABSTRACT FROM AUTHOR]

The research domain of underwater communication has garnered much interest among researchers exploring underwater activities. The underwater environment differs from the terrestrial setting. Some of the main challenges in underwater communication are limited bandwidth, low data rate, propagation delay, and high bit error rate (BER). As such, this study assessed the underwater acoustic (UWA) aspect and explored the expression of error performance based on t‐distribution noise. Filter orthogonal frequency‐division multiplexing refers to a new waveform candidate that has been adopted in UWA, along with turbo and polar codes. The empirical outcomes demonstrated that the noise did not adhere to Gaussian distribution, whereas the simulation results revealed that the filter applied in orthogonal frequency‐division multiplexing could significantly suppress out‐of‐band emission. Additionally, the performance of the turbo code was superior to that of the polar code by 2 dB at BER 10−3. [ABSTRACT FROM AUTHOR]

In this Letter, a new scheduling scheme for belief propagation (BP) is proposed to reduce the decoding latency. All the stages update messages at the same time, it improves the reliability and accelerates the decoding convergence. The authors also remove the last stage of factor graph to reduce computational complexity. Simulations show that the average decoding latency of a (1024,512) polar code is reduced to 29.4 clocks. [ABSTRACT FROM AUTHOR]

Non‐data‐aided (NDA) carrier phase recovery (CPR) is one of simple CPR algorithms which simply rotates received symbols to the nearest constellation point. Unfortunately, when the NDA CPR is used with M‐ary phase shift keying, it suffers inherent M‐fold phase ambiguity and thus the phase ambiguity must be resolved. On the other hand, the generator matrix of polar code G can be obtained with the Kronecker product of a 2×2 lower triangular matrix. Hence, the Hamming weights of all columns of G are given by non‐negative integer powers of 2. Based on this observation, an 180° rotationally invariant polar code suitable for digital communication systems employing binary phase shift keying and NDA CPR is proposed. The proposed polar code offers virtually identical performance under both 0° and 180° carrier phase offsets to that of conventional polar code with perfect CPR with identical encoding and decoding complexities. [ABSTRACT FROM AUTHOR]

A polar code‐based overlapping transmission scheme to improve channel utilisation for Internet of Vehicles is presented. In the presented scheme, different relay nodes (RNs) are allowed to send their packets to the destination node (DN) in the same time slot and frequency band. The signals from RNs to DN are overlapped and hence non‐orthogonal. However, the information in the overlapped signals can be recovered by the proposed decoding algorithm. Numerical results show that the decoding algorithm performs well on information recovery in the presented transmission scheme. [ABSTRACT FROM AUTHOR]

Since the polar code was discovered by Arikan, many decoding methods have been proposed, one of which is the belief propagation (BP) decoding. Its inherent high parallel level makes it suitable for high‐speed applications. A novel BP decoder based on a modified three‐by‐three kernel matrix is proposed. The corresponding decoding algorithm and frozen bits selection method are presented. The numerical results show that it has a similar error correcting capability compared with the original polar BP decoder. More importantly, the message memory requirement can be reduced from O(N log2N) to O(N log3N), and the decoding delay can be reduced accordingly. [ABSTRACT FROM AUTHOR]

A new architecture for a polar decoder using a reduced complexity successive‐cancellation (SC) decoding algorithm is presented. This novel fully unrolled, deeply pipelined architecture is capable of achieving a coded throughput of over 237 Gbit/s for a (1024, 512) polar code implemented using a field‐programmable gate array. This decoder is two orders of magnitude faster than state‐of‐the‐art polar decoders. [ABSTRACT FROM AUTHOR]