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The revised critical set (RCS) used by successive cancellation list flip (SCLF) decoding algorithm only retains the unreliable bits of SC state. So, the bits of information in the RCS are not comprehensive enough. Aiming at this problem, this paper proposed a kind of complete state critical set (CSCS) based SCLF decoding algorithm for polar codes. In order to obtain a more complete flipping set of states, the proposed CSCS is constructed according to different path splitting states after pruning. According to different states of CSCS, hard decision and path metric (PM) correction methods are adopted respectively, to cut off the wrong path and keep the correct path, so as to achieve bit flipping function. Experimental results show that compared with the traditional SCLF decoding algorithm, the performance of complete state SCLF (CS-SCLF) decoding algorithm is improved. At the same time, the average flipping number of flips is reduced without loss of decoding performance. [ABSTRACT FROM AUTHOR]

In modern wireless communication systems, the efficient transmission of high-quality images is a matter of paramount importance. In recent several years, compressed sensing (CS) has emerged as a powerful technique for reducing the energy consumption, improving the data compression, and lowering the bandwidth requirements for an image transmission. However, communication channels, especially wireless channels, often introduce various forms of interferences and fading, such as Rayleigh fading, which can severely degrade the received image quality. This paper proposes a novel approach that combines compressed sensing with polar code to improve the reliability of image communication through a Rayleigh fading channel. In this work first, we leverage the advantages of compressed sensing to significantly reduce the amount of data that needs to be transmitted while maintaining acceptable image quality. By exploiting sparsity of the standard images, we can sample and compress the images efficiently. Next, we have applied polar code, known for its superior error correction capabilities, to protect the compressed data from channel induced errors. The paper presents a comprehensive evaluation of the proposed system, including theoretical performance bounds and simulations in a Rayleigh fading channel. Our results demonstrate that the combination of compressed sensing and polar coding outperforms traditional communication schemes in terms of both optimal bandwidth requirement and image quality in the form of its reliability under challenging fading environments. This approach offers a promising solution for efficient and robust image transmission over wireless channels, with applications in remote sensing, surveillance, medical imaging, and many more. This paper focuses on choosing an optimum error correction scheme tailored for compressed sensing signals under severe channel conditions. The performance of the reconstructed image has been evaluated based on the performance parameters such as peak signal-tonoise ratio (PSNR), structural similarity (SSIM) index and bit error rate (BER) under multipath fading conditions. Simulation results show the superior performance of the proposed model at a very low signal-noise ratio (SNR) in the range of 2.5 to 3.6 dB. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we investigate the decoding performance and corresponding decoding strategies for polar-coded orthogonal frequency division multiplexing (OFDM) system operating under multipath fading channels. Multipath fading channels lead to frequency selective fading of the OFDM signal, resulting in varying levels of noise interference across different subcarriers after equalization. Furthermore, frequency selective fading induces burst errors in the equalized information, thereby significantly degrading the decoding performance. To address these issues, we propose two schemes in this paper to enhance the decoding performance of polar-coded OFDM system. Firstly, we integrate the channel state information of each subcarrier into the generation of soft information for the polar codes decoder, in order to alleviate the degradation of decoding performance caused by variations in signal-to-noise ratio across subcarriers during OFDM demodulation. Secondly, we introduce a packet interleaving design after the polar codes encoder to enhance the robustness of polar codes against burst errors. Simulation results demonstrate that the combined application of these two decoding strategies significantly outperforms the conventional scheme in terms of transmission performance over multipath fading channels. The findings of this study suggest that, within the context of future wireless communication systems utilizing Polar-OFDM, the concurrent implementation of our two proposed decoding strategies is essential for achieving robust error correction performance in the OFDM system.

To improve the decoding performance of the simplified sequence repetition node-based fast successive cancellation (SSRFSC) decoding algorithm, a decoding algorithm (CSS-SSR-Flip) based on critical simplified set (CSS) and simplified sequence repetition (SSR) nodes was designed. Firstly, the information bit of the longest repetition (REP) node in SSR was selected as candidate bit (CB), thus constructing a CSS based on SSR. Corresponding flip metrics and flip criterion were designed according to the decoding characteristics of SSR nodes. Secondly, the CB reliability was measured by considering the influence of repetition sequences and the source of SSR nodes on decoding, and suboptimal repetition sequences were selected to complete SSR node flip operations during specific CB flips. Experimental data shows that at frame error rates of 10-3, CSS-SSR-Flip decoding algorithm is able to obtain more than 0.1 dB performance gain compared to the traditional fast simplified successive cancellation filp (Fast-SSC-Flip) decoding algorithm, and has the same decoding performance as the new Fast-SSC-Flip (New-Fast-SSC-Flip) decoding algorithm. However, compared to the traditional flip set size K, the CSS size of the proposed algorithm is reduced by up to 79.5%, and compared to the critical set (CS), the set size can be reduced by up to 23.1%.

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Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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, singlestage 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 paritycheck 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 errorcorrecting performance and better hardware efficiency makes our decoder a suitable alternative to the successive cancellation list decoders used in 5G wireless communication.

The article explores a recursive algorithm for determining Bhattacharyya parameters, which is a measure of the degree of channel polarization for telecommunications with polar coding. A method is given for determining the positions of information and fixed bits in a polar code. The principles of constructing a polar encoder and a polar decoder successive cancellation are considered. The Field-Programmable Gate Array implementation of the successive cancellation list decoder is considered. Experimental studies of the construction of a polar code using Gaussian approximation have been carried out. The influence of the design signal-to-noise ratio on the bit error rate of telecommunications with polar codes has been studied. The use of multi-position modulation in telecommunications with polar codes has been studied. It is expected that the results obtained will be useful in hardware and software implementation of 5G telecommunications with polar coding.

Polar codes are the popular error-correcting codes and increased their attention after being adopted for the control channel in fifth-generation new radio (5G NR) standards. An efficient hardware architecture for polar code is often required with minimal encoding and decoding complexity. This work proposes a Multi-folded pipelined architecture and analyzes the performance in terms of latency, hardware utilization, and throughput. The designed architecture has two folded architectures interconnected in parallel to output 4-bits simultaneously. Folding transformations are used to reduce the number of idle processing elements (PEs) in every stage leading to the effective utilization of PE. Precomputation is effectively utilized in the PE to reduce the critical path delay, which improves the maximum operating frequency. A Loop-based shifting register (LSR) is employed to reduce the number of registers used. The analytical model for latency and utilization rate has been derived from the scheduling of the proposed architecture. The proposed design shows 63–71% higher hardware utilization than conventional semi-parallel design for code length N = 512 suitable for the physical downlink control channel (PDCCH) in 5G NR. The architecture is also implemented in Virtex-6, ZYNQ-Ultrascale+ MPSoC device for maximum supported code length of 5G NR, i.e., up to 2 10 , compared with the existing decoders. The proposed design also has the benefit of lesser look-up-table (LUT) consumption and zero random-access-memory (RAM) usage with some additional registers, making it suitable for resource-constraint applications. [ABSTRACT FROM AUTHOR]

In digital baseband processing, the forward error correction (FEC) unit belongs to the most demanding components in terms of computational complexity and power consumption. Hence, efficient implementation of FEC decoders is crucial for next-generation mobile broadband standards and an ongoing research topic. Quantization has a significant impact on the decoder area, power consumption and throughput. Thus, lower bit widths are preferred for efficient implementations but degrade the error correction capability. To address this issue, a non-uniform quantization based on the Information Bottleneck (IB) method is proposed that enables a low bit width while maintaining the essential information. Many investigations on the use of the IB method for Low-density parity-check code) LDPC decoders exist and have shown its advantages from an implementation perspective. However, for polar code decoder implementations, there exists only one publication that is not based on the state-of-the-art Fast Simplified Successive-Cancellation (Fast-SSC) decoding algorithm, and only synthesis implementation results without energy estimation are shown. In contrast, our paper presents several optimized Fast-SSC polar code decoder implementations using IB-based quantization with placement and routing results using advanced 12 nm FinFET technology. Gains of up to 16% in area and 13% in energy efficiency are achieved with IB-based quantization at a Frame Error Rate (FER) of 10 − 7 and a polar code of N = 1024 , R = 0.5 compared to state-of-the-art decoders. [ABSTRACT FROM AUTHOR]

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]

Copyright of Journal of Chongqing University of Posts & Telecommunications (Natural Science Edition) is the property of Chongqing University of Posts & Telecommunications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The 3-D TLC NAND flash memory significantly increases the storage capacity but makes data more prone to errors. To address the reliability problem, Polar Code is one coding method that can reach the channel capacity (Arikan 2009). However, the 3-D NAND flash memory channel is uncertain due to the variation of retention time and program/erase(P/E) cycle. So it is difficult to construct a Polar Code in the NAND flash memory. This letter proposes a new Polar Code construction method called dynamic merge Monte Carlo (DMMC). DMMC uses the Monte Carlo method to obtain the optimal Polar Code construction and then reduces the space overhead by combining similar construction so that it can be used in flash memory systems. Compared with the conventional method, the uncorrectable bit error rate (UBER) of the proposed method can reduce by up to 90.5%, and the read latency can reduce by more than 50%. [ABSTRACT FROM AUTHOR]

This paper proposes a novel medical image watermarking scheme for a multiuser wireless system based on data normalization and polar code. The watermark image is normalized, converted into a set of coefficients using Discrete Cosine Transform (DCT), and then embedded with host medical image coefficients. The watermark image is encrypted using a Baker map and then normalized. The normalized value is converted to binary data, then XORed with a logistic map sequence, and employed as frozen bits in polar code to achieve security, robustness, and imperceptibility over the Non-Orthogonal Multiple Access-Universal Filtered Multicarrier (NOMA-UFMC) transmission scheme. A collection of medical images was employed to evaluate the proposed technique for two users, and the findings are Peak Signal to Noise Ratio (PSNR=69.5761), structural similarity index (SSIM=0.9966), mean square error (MSE=0.4399) and Normalized Cross-Correlation (NCC=0.9997) which demonstrate that it is capable of achieving a high level of imperceptibility and robustness against attacks. In addition, the proposed scheme produced good Bit Error Rate (BER) performance by exploiting the properties of polar code. Compared with the traditional techniques, the proposed approach has higher image quality, a secure watermark image, performs high robustness against various attacks, and has low execution time (about 0.3284 seconds). The suggested method is, therefore, a promising one for protecting medical images in healthcare settings. [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 pro-pose a polar code scheme based on Plotkin structure and quasi-uniform punching (PC-QUP). Then we apply the PC-QUP to coded-cooperative sce-nario 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 pro-posed cooperative PCC-QUP-STBC scheme can obtain a lower bit error ratio (BER) than its corresponding noncooperative scheme.

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]

Multipath channels continue to present challenges in wireless communication for both 5G and 6G networks. A multipath channel is a phenomenon in wireless communications where signals traverse from the sender to the receiver along various paths. This end occurs due to the reflection, diffraction, and refraction of signals of various objects and structures in the environment. Such pathways can cause symbol interference in the transmitted signal, leading to communication issues. To this end, our paper proposes the integration of three algorithms: teaching-learning-based optimization (TLBO), particle swarm optimization (PSO), and artificial neural networks (ANN). This combination effectively analyzes and stabilizes the transmission channel, minimizing symbol interference. We have developed, simulated, and evaluated this hybrid approach for multipath fading channels. We apply it to various coding schemes, including tail-biting convolutional code, turbo codes, low-density parity-check, and polar code. Additionally, we have explored various decoding methods such as Viterbi, maximum logarithmic maximum a posteriori, minimum sum, and cyclic redundancy check soft cancellation list. Our study encompasses new channel equalization schemes and coding gains derived from simulations and mathematical analysis. Our proposed method significantly enhances channel equalization, reducing interference and improving error correction in wireless communication systems. [ABSTRACT FROM AUTHOR]

To accomplish the targets of Beyond Fifth-Generation (B5G) networks, considerable spectral efficiency, wide coverage, better reliability, and energy efficiency are the main objectives. In order to enhance the performance of the Orthogonal Frequency Division Multiplexing (OFDM) signal in terms of Bit Error Rate (BER), powerful channel coding, such as polar coding, must be considered. In addition, a Massive Multi-Input Multi-Output (MMIMO) combined with OFDM can support better performance and spectral efficiency. On the other hand, Physical Layer Network Coding (PLNC) can increase system throughput. This paper explores the integration of Polar-Coded OFDM (PCOFDM) with MMIMO and PLNC to enhance transmission reliability and throughput. A two-way relay transmission scenario is considered at millimeter Wave (mmWave) frequencies. The consequences of the extensive simulation assessments for Multilevel Quadrature Amplitude Modulation (M-QAM) demonstrated that refinements in throughput and BER can be performed using PCOFDM, with PLNC having enough antenna elements in the massive MIMO system at the base station (the relay node). In any case of the number of antenna elements utilized in the user terminal, the BER achievement of PCOFDM-MMIMO with PLNC surpassed that of a similar system without polar code (antenna elements used in the base station are 128 and 256). [ABSTRACT FROM AUTHOR]

Due to diminishing ice shelves in the Arctic, no doubt caused by climate change, previously unnavigable marine spaces are opening up, which in turn may provide new maritime routes. The shipping and maritime industry may capitalise on these routes more in the future as they provide shorter sailing times, and may assist with increasing oil and gas exploration and extraction in the region. However, increased maritime expansion in the Arctic comes with a number of unique risks and hazards for the insured and insurer. This opinion therefore seeks to discuss the implications of the multitude of risks that are associated with Arctic shipping from a marine insurance perspective and to highlight some of the gaps in existing regulatory frameworks. It is argued that marine insurers require improved data and risk management methodologies in order to better calculate the premiums of Hull & Machinery (H&M) and Protection & Indemnity (P&I) insurance policies for ships travelling through the Arctic. Until such time as these risks can be adequately assessed, evaluated, and managed by insurers; which of course is extremely difficult, due to the extreme environment, the unpredictability of climate change, a lack of key data, and the complexity of the various scenarios that can unfold in the Arctic environment, the practical viability of Arctic shipping remains doubtful. To date, insurers have paid out more in ship damage that has occurred in the Arctic than they have collected in premiums, which in itself is problematic. This situation may change in the future if Arctic shipping grows, and if it does the insurance market will no doubt, need to respond. [ABSTRACT FROM AUTHOR]

The coding of channels is a core part of any communication network. Future wireless systems will need high performance codes with low complexity encoding and decoding in order to meet a wide variety of requirements, from running in highly dependable situations with short information messages and low code rates to running in high throughput scenarios with lengthy messages and high code rates. The investigation of polar codes in fading channels has important implications in the context of implementing polar codes in wireless communications. A significant development in the fields of information and coding theory, polar code allows for the flexible adjustment of code rates and block lengths without compromising error correction efficiency. Recently, the Third Generation Partnership Project (3GPP) New Radio (NR) group has supported polar codes to provide channel coding in the physical control channels of the 5G, wireless standard. Channel coding, which exists inside the physical layer, is essential in determining the latency and dependability of a communication system. However, error correction performance diminishes with shorter message durations. The polar encoding scheme can achieve channel capacity because it is based on the practical use of channel polarization operation. In this research, a polar code is included in the proposed system for data transmission over various multipath fading channel models (Nakagami-m, Rayleigh, and Lognormal fading channels) in the presence of AWGN, and in this design, the Successive Cancellation List (SCL) decoding algorithms for polar code are used in order for the suggested NR-polar QAM-OFDM system to perform better than the uncoded QAM-OFDM system. According to Monte Carlo simulations, QAM constellation NR-Polar-COFDM using LLRs computed due to the normal distribution over different types of channel PDFs performs better than the uncoded QAM-OFDM system in terms of bit error rat BER. To further enhance the system performance, CRC bits are used to enhance the efficiency of SCL decoding by improving distance characteristics. The simulation results show that BER is approximately 10-6 at SNR of 1dB in the AWGN channel, and in the multipath fading channel BER approaches 10-6 at SNR of 22.5dB in the Rayleigh and Nakagami-m fading channels, while in the lognormal fading channel at SNR of 14dB for short information block lengths at code rates (1/3) in the uplink and downlink control channels. The findings additionally confirm the superiority of Polar coding in the situation of transmitting information with short block lengths in the AWGN compared to the NR-LDPC-OFDM. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chongqing University of Posts & Telecommunications (Natural Science Edition) is the property of Chongqing University of Posts & Telecommunications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Underwater environment is still an attractive area to explore and exploit by human beings. However, underwater characteristics limit communications due to harsh channel conditions, and efficient channel codes are essential to deploy. This study presents an underwater system based on protograph low-density parity check (P-LDPC) codes and orthogonal frequency division multiplexing (OFDM) for image transmission. The system proves a successful reconstruction of P-LDPC coded images with different levels of comparison. The performance of the proposed system is evaluated using nine objective measures such as bit error rate (BER) and peak signal to noise ratio (PSNR). Firstly, the proposed system performance is evaluated with different block lengths of P-LDPC code. Then, the implemented system shows a coding gain of approximately 1.75 dB for applying P-LDPC when compared to polar with cyclic redundancy check at 0.0001 BER. Additionally, image subjective assessment is obtained to demonstrate how the P-LDPC outweighs polar and turbo product codes in terms of estimated image quality. Lastly, further investigation is performed to study the effect of varying fast Fourier transform (FFT) size and cyclic prefix (CP) length on image reserved quality. The results show that the received image is better reconstructed for larger FFT sizes since that produce longer CP and symbol duration, and that in turn helps the system to combat the multipath fading introduced by the underwater channel.

Protecting ownership of digital content is challenging in today’s online world, especially when sharing content through social networks and instant messengers. One possible solution is the use of watermarking; however, if the watermarking method is not robust enough, the watermark can get damaged or erased during transmission. This study introduces a template-based watermarking method with neural network-based extraction, strengthened by error-correcting polar codes, that is designed to work well on major social networks like Facebook, Facebook Messenger, VK, Telegram, Snapchat, Pinterest, and WhatsApp. The method can embed imperceptible (PSNR=39.66) watermarks ranging from 650 to 1600 bits for high-definition images (1920-by-1080 pixels) with small probability (0.01) of erroneous extraction after being transferred through social networks. The key feature of the method is its ability to work with real communication channels, as shown during its testing.

One of the main issues facing in the future wireless communications is ultra-reliable and low-latency communication. Polar codes are well-suited for such applications, and recent advancements in deep learning have shown promising results in enhancing polar code decoding performance. We propose a robust decoder based on a bidirectional long short-term memory (Bi-LSTM) network, which processes sequences in both forward and backward directions simultaneously. This approach leverages the strengths of bidirectional recurrent neural networks to improve the decoding of polar-coded short packets. Our study focuses on packet transmission over frequency-flat quasi-static Rayleigh fading channels, using a simple codebook originally designed for additive white Gaussian noise channels. We evaluate the packet error rate for various signal-to-noise ratio levels using different modulation schemes. The simulation results demonstrate that the proposed Bi-LSTM-based decoder closely approaches the theoretical outage performance and achieves significant coding gains in fading channels. Furthermore, the proposed decoder outperforms convolutional neural network and deep neural network-based decoders, validating its superiority in decoding polar codes for short packet transmission in challenging wireless environments.

Polar codes are one of the most powerful types of forward error correction codes. These codes are now adopted in the 5G standard for control channels and are the primary contender for future communication systems. In this paper, a new data transmission system is proposed using adaptive rate non-systematic polar code and adaptive Hierarchical Quadrature Amplitude Modulation (HQAM) to improve the error performance of the system according to the channel quality over Gaussian and Rician channels. To determine the high and low priority bits for HQAM, a new algorithm is proposed in case of non-systematic polar code where the information bits are inherited in the codeword. In the proposed system, both polar code rate and HQAM parameter constellation distances are adaptive according to the channel quality and target block error rate to enhance the spectral efficiency. Since HQAM does not change the modulation order, then the proposed system offers same demodulator complexity in contrast to traditional adaptive modulation with various modulation orders. Simulation results prove that the proposed system achieves the target block error rate at lower bit energy to noise power spectral density ratio, in addition to better spectral efficiency compared to adaptive rate polar code with traditional QAM system. Moreover, the proposed system achieves superior spectral efficiency than fixed coding and modulation system and traditional adaptive modulation and coding system.

Nowadays, the advancement and increased use of fifth-generation (5G) and sixth-generation (6G) systems have created a demand for more efficient and rapid transmission of information over wireless communication media. However, developing wireless communication systems that can meet these modern-day criteria for fast, reliable, and secure information exchange is a challenging task. To address this issue, this paper proposes a novel model for enhancing the 5G system. The proposed model utilizes polar code with rate matching and constitutional interleaving over the Suzuki fading channel. The combination of polar codes with rate matching and interleaving enables the communication system to achieve a lower error rate and better reliability over a Suzuki fading channel. Specifically, the polar code can correct a larger number of errors, while rate matching and interleaving can mitigate the effects of channel variations and reduce the probability of error bursts. These enhancements can lead to more robust and reliable communication in wireless networks.

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to optimize the implementation complexity and information transmission speed of the fifth generation communication technology, the Polar code based on channel polarization phenomenon gradually receives great attention and research, and forms many industry standards and research conclusions. In recent years, the development and optimization of Polar code encoding and decoding technology promotes the popularity of the fifth generation communication technology, and the rapid application of the new generation communication technology greatly promotes the further iteration of the underlying encoding and decoding technology. By reviewing the research history of Polar code encoding and decoding technology, the research status and context of Polar code encoding and decoding technology in the fifth generation communication are summarized. On this basis, the problems and requirements of current coding and decoding theory are analyzed and discussed in depth, and the research ideas and trends of the underlying coding and decoding theory in the future communication technology are proposed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

In order to solve the problems of low transmission performance, inaccurate flip set construction and high complexity of existing polar codes successive cancellation list bit-flip (SCLF) algorithms, a SCLF algorithm for polar codes based on GRU network assistance and path metric exchange was proposed.First the decoding state was redivided, and a bit-flip strategy was proposed by combining the ideas of path metric exchange and reverse judgment.Secondly, a flip set construction method was proposed by training the GRU network to locate the first erroneous bit in the decoding.Finally, a multi-bit flipping rule was proposed by sorting the path metric for each low-order flip and fixing the low-order reliable bits before performing the high-order flip.Simulation results show that compared with the existing SCLF algorithms, the proposed algorithm improves the accuracy of identifying the first error bit by 18～24% at low signal noise ratio.Under single-bit and multi-bit flipping, the proposed algorithm has a performance gain of up to 0.3 dB and 0.2 dB, respectively, and the online decoding complexity is lower.

In order to reduce the decoding latency of the successive cancellation (SC) decoding algorithm further, a kind of fast SC decoding algorithm based on simplified sequence repetition (SR) nodes, namely simplified sequence repetition node-based fast SC (SSRFSC), was proposed to optimize decoding latency issues of SC decoding algorithm.Different types of extended class of generalized parity-check (EG-PC) nodes were decomposed, merged and simplified based on the type of SR source node and decoding complexity, and Rate-C node was trimmed using fast simplified successive cancellation (Fast-SSC) decoding.Experimental results show that the decoding latency of the proposed algorithm can be reduced by up to 28% compared to the latest simplified sequence repetition (SRFSC) decoding algorithm when achieving similar decoding performance (approximately 0.1dB performance loss at frame error rate of 10-3).Moreover, compared to the Fast-SSC decoding algorithm, the decoding latency of proposed algorithm can be reduced by up to 49%.

In this paper, we propose a pre-configured error pattern ordered statistics decoding (PEPOSD) algorithm and discuss its application to short cyclic redundancy check (CRC)-polar codes. Unlike the traditional OSD that changes the most reliable independent symbols, we regard the decoding process as testing the error patterns, like guessing random additive noise decoding (GRAND). Also, the pre-configurator referred from ordered reliability bits (ORB) GRAND can better control the range and testing order of EPs. An offline–online structure can accelerate the decoding process. Additionally, we also introduce two orders to optimize the search order for testing EPs. Compared with CRC-aided OSD and list decoding, PEPOSD can achieve a better trade-off between accuracy and complexity. [ABSTRACT FROM AUTHOR]

To solve the problem of blind identification of channel coding in signal interception and intelligent communication systems, a blind recognition algorithm of channel coding based on a convolutional neural network (CNN) is proposed. To deal better with the input characteristics of one-dimensional soft decision sequences under the low SNR regime, we design and construct a low-complexity one-dimensional CNN classifier. Firstly, the dataset of five types of channel codes is generated, including linear block codes, Turbo codes, convolutional codes, LDPC codes and Polar codes. Secondly, the one-dimensional CNN classifier is initialized and imported into the database. Thirdly, the training dataset.mat file generated in matlab is imported into the convolutional neural network, and the dataset of five types of channel codes is labeled. Finally, a one-dimensional convolutional neural network model is established, and the dataset in the model is compiled and trained, the training data tags in the model are predicted and the confusion matrix is saved. The simulation results show that the proposed algorithm expands the recognition range of existing types of channel codes, and for the first time completes the blind recognition of five types of channel codes. Compared with the traditional algorithm LSTM (Long Short Term Memory), the algorithm proposed in this paper has lower complexity, the recognition rate can be kept 92% when the SNR is 0 dB, and the performance is improved by 24%. [ABSTRACT FROM AUTHOR]

The existing parameter recognition algorithms for non-punctured polar codes default the frozen bit values to 0, and do not have the ability to judge the frozen bit values. Aiming at this problem, the parity check relation between codeword matrix and column vectors of generator matrix is deduced, where the identification of bit type and the judgment of frozen bit value are converted into a test of the check relationship. Based on the above, the average likelihood difference is introduced as a statistic volume, and the theoretical distribution and decision threshold of the statistic volume are given. The algorithm uses the proportion of information positions in the decision result to identify the parameters such as code rate and code length. Simulation experiments show that the derivation of the relevant properties is consistent with the actual situation. The proposed algorithm overcomes the shortcomings of existing methods that cannot identify frozen bit values on the basis of the same computational complexity level and without reducing the recognition performance. When the signal to noise ratio is 5. 5 dB, the recognition accuracy is still close to 100% for polar codes with a code length of 512 of the polar code. [ABSTRACT FROM AUTHOR]

Abstract To further accelerate the practical process of polar codes in underwater acoustic communication (UWC) and improve the reliability and efficiency of underwater data transmission, we first propose a polar code construction method suitable for the underwater acoustic channel, which drastically reduces the complexity and meets the need for practical UWC. Then, we establish a practical polar coded UWC scheme by devising a two-step procedure based on the Orthogonal Frequency Division Multiplexing technique. Moreover, through simulation, the scheme's performances with the unimproved and the proposed polar code construction method are analyzed. Moreover, its performances with four different polar decoders are also given. The performance comparison with the LDPC coded UWC system is studied as well. Furthermore, lake-trial results under two different channel conditions demonstrate that the proposed construction method and the scheme effectively guarantee the reliability of data transmission, achieving error-free transmission at a transmission distance of 1718 m with the signal-to-noise-ratio (SNR) of 21 dB, and a transmission distance of 749 m with the SNR of 16.5 dB, better than the LDPC coded system with same conditions. The semi-experimental results show that the proposed polar coded system under the Cyclic Redundancy Check-Aided Successive Cancellation List decoder outperforms the LDPC coded system by approximately 2.1–3.7 dB.

The opening of the Arctic Sea routes ushers in many opportunities due to the melting of the Arctic Sea ice. The International Maritime Organization has introduced the Polar Code for shipping and training of seafarers. Follow up by regulatory authorities of incidents along with the Northern Sea Route and in-creasing ship casualties in the Arctic region have been analyzed, including the adequacy of existing regula-tions. The author’s opinion is that the inadequate oversight mechanism brings out a need for governments of the Arctic, especially in Russia, to examine the adequacy of measures undertaken, including regulation to implement the Polar code, associated infrastructure in the Arctic for safe navigation and the current state of search and rescue. The challenges in implementing the Polar Code and the necessity for independent maritime regulatory authorities and sharing information relating to the analysis of incidents are discussed. The practical significance of the article is in its use by policymakers and researchers working on transport policy and safety of Arctic navigation, and also for educational use at universities.

Semantic communication is considered the future of mobile communication, which aims to transmit data beyond Shannon’s theorem of communications by transmitting the semantic meaning of the data rather than the bit-by-bit reconstruction of the data at the receiver’s end. The semantic communication paradigm aims to bridge the gap of limited bandwidth problems in modern high-volume multimedia application content transmission. Integrating AI technologies with the 6G communications networks paved the way to develop semantic communication-based end-to-end communication systems. In this study, we have implemented a semantic communication-based end-to-end image transmission system, and we discuss potential design considerations in developing semantic communication systems in conjunction with physical channel characteristics. A Pre-trained GAN network is used at the receiver as the transmission task to reconstruct the realistic image based on the Semantic segmented image at the receiver input. The semantic segmentation task at the transmitter (encoder) and the GAN network at the receiver (decoder) is trained on a common knowledge base, the COCO-Stuff dataset. The research shows that the resource gain in the form of bandwidth saving is immense when transmitting the semantic segmentation map through the physical channel instead of the ground truth image in contrast to conventional communication systems. Furthermore, the research studies the effect of physical channel distortions and quantization noise on semantic communication-based multimedia content transmission.

Polar code is a recent forward error correction technique that is characterized by its low encoding/decoding complexity and good error performance. In this paper, a complete image transmission system (transmitter and receiver) is proposed to improve the image quality over different types of channels such as Gaussian, Rayleigh and Rician channels. The proposed system is based on encoding the most significant quantized Discrete Cosine Transform (DCT) coefficients of the digital image using adaptive rate polar coding, by changing the number of frozen bits depending on the number of significant DCT coefficients that depend on the channel quality. Simulation results reveal that the proposed system achieves better performance compared to the coded digital transmission schemes in terms of the Structural SIMilarity (SSIM) index and the Peak Signal to Noise Ratio (PSNR) for different sizes of images. Moreover, it is not subject to “cliff effect” and exhibits improvement in image quality according to the channel quality.

In the conventional successive cancellation (SC) decoder for polar codes, all the future bits to be estimated later are treated as random variables. However, polar codes inevitably involve frozen bits, and their concatenated coding schemes also include parity bits (or dynamic frozen bits) causally generated from the past bits estimated earlier. We refer to the frozen and parity bits located behind a target decoding bit as its future constraints (FCs). Although the values of FCs are deterministic given the past estimates, they have not been exploited in the conventional SC-based decoders, not leading to optimality. In this paper, with a primary focus on the binary erasure channel (BEC), we propose SC-check (SCC) and belief propagation SCC (BP-SCC) decoding algorithms in order to leverage FCs in decoding. We further devise an improved tree search technique based on stack-based backjumping (SBJ) to solve dynamic constraint satisfaction problems (CSPs) formulated by FCs. Over the BEC, numerical results show that a combination of the BP-SCC algorithm and the SBJ tree search technique achieves the erasure recovery performance close to the dependence testing (DT) bound, a bound of achievable finite-length performance.