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rateless coding on Experimental Temporally Correlated FSO Channels

JOURNAL OF LIGHTWAVE TECHNOLOGY 2010年第7期28卷 990-1002页

作者： Anguita, Jaime A. Neifeld, Mark A. Hildner, Bjoern Vasic, Bane Univ Los Andes Coll Engn & Appl Sci Santiago 7620001 Chile Univ Arizona Dept Elect & Comp Engn Tucson AZ 85719 USA Univ Arizona Coll Opt Sci Tucson AZ 85719 USA

We present a demonstration of two error-correction coding schemes that can successfully operate on a free-space optical (FSO) communication channel subject to atmospheric turbulence. The codes (a puntured Low-density parity-check code and a Raptor code) operate by continuously adapting the information rate to accommodate the varying channel conditions. Because these coding schemes require the use of a feedback channel, we evaluate the bandwidth cost incurred. The evaluation of the codes is performed offline and uses experimental optical signals recorded from an FSO link. We analyze the temporal characteristics of the experimental channels and compare the performance of the codes for different bit rates to asses the effect of temporal correlation and imperfect channel state information.

关键词： Atmospheric turbulence error-correction coding free-space optical (FSO) communication laser applications optical communication rateless coding soft decoding time-varying channels

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rateless coding for wireless relay channels

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2007年第5期6卷 1638-1642页

作者： Castura, Jeff Mao, Yongyi Univ Ottawa SITE Ottawa ON K1N 6N5 Canada

We propose a novel coding framework for wireless relay channels based on rateless codes, which allows for a natural extension to multiple antenna and multiple relay settings. The relaying protocol is half-duplex, and relays independently choose when to collaborate, if at all. With a simulated fountain code based implementation of this framework, we show that the use of rateless codes is both robust and efficient when the channel state information is not available at the transmitters.

关键词： channel coding cooperative diversity rateless coding relay networks

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rateless coding Schemes Using Polar Codes: Truly "No" Rates?

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IEEE ACCESS 2020年 8卷 2428-2440页

作者： Liang, Hao Liu, Aijun Gong, Chao Liu, Xian Army Engn Univ PLA Coll Commun Engn Nanjing 210007 Peoples R China

In this paper, aiming to achieve rate adaptation for the rateless coding (RC) schemes of polar codes, we explore their throughput efficiency and optimize a series of rates that are set in two types of RC schemes. First, the RC scheme with incremental freezing (IF-RC) decoding is analyzed from the perspective of rate matching. Then, a new RC scheme based on extending codes and copying information bits (termed EC-RC) is developed in detail. Moreover, to overcome the drawback of an undefined rate sequence in RC transmission, rate optimization strategies are separately proposed for both IF-RC and EC-RC by maximizing throughput efficiency with dynamic programming. Closed-form expressions of throughput for these two RC methods are derived as a consequence. The optimization procedure can be realized in practice with low complexity. Finally, the numerical results and analyses demonstrate that rate adaptation of polar-coded RC can be achieved along with maximum throughput by our proposed strategies over both AWGN channels and Rayleigh fading channels. The two optimized RC schemes provide higher throughput efficiency than other existing rateless codes.

关键词： Polar codes rateless coding throughput rate adaptation optimization

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rateless coding for Hybrid Free-Space Optical and Radio-Frequency Communication

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2010年第3期9卷 907-913页

作者： AbdulHussein, Ali Oka, Anand Nguyen, Trung Thanh Lampe, Lutz Univ British Columbia Dept Elect & Comp Engn Vancouver BC V5Z 1M9 Canada

Free-space optical (FSO) transmission systems enable high-speed communication with relatively small deployment costs. However, FSO suffers a critical disadvantage, namely susceptibility to fog, smoke, and conditions alike. A possible solution to this dilemma is the use of hybrid systems employing FSO and radio frequency (RF) transmission. In this paper we propose the application of a rateless coded automatic repeat-request scheme for such hybrid FSO/RF systems. The advantages of our approach are (a) the full utilization of available FSO and RF channel resources at any time, regardless of FSO or RF channel conditions and temporal variations, and (b) no need for a-priori rate selection at the transmitter. In order to substantiate these claims, we establish the pertinent capacity limits for hybrid FSO/RF transmission and present simulation results for transmission with off-the-shelf Raptor codes, which achieve realized rates close to these limits under a wide range of channel conditions. We also show that in conditions of strong atmospheric turbulence, rateless coding is advantageous over fixed-rate coding with rate adaptation at the transmitter.

关键词： Free-space optical (FSO) hybrid FSO/RF transmission rateless coding channel capacity

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rateless coding Scheme for Time-Varying Dying Channels 8

Rateless Coding Scheme for Time-Varying Dying Channels

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8th International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Wang, Yang Jiao, Jian Sui, Xindong Wu, Shaohua Li, Yonghui Zang, Qinyu Harbin Inst Technol Shenzhen Grad Sch Commun Engn Res Ctr Harbin Heilongjiang Pr Peoples R China Univ Sydney Sch Elect & Informat Engn Sydney NSW 2006 Australia

ISBN: (纸本)9781509028603

In spatial information networks (SIN), communication links are suffered by periodic time-varying channel noise because of the periodic motion orbit of the space nodes and planets. Moveover, SIN communications may have a probability to fail at random times, such as severe rain attenuation on Ka band downlinks, or solar scintillation during the superior/inferior solar conjunction. In this paper, we propose a time-vary dying channel with finite channel-length and Rician fading to model this SIN channels, and the upper and lower bounds of outage capacity are derived. Furthermore, we propose a sub-optimal distribution rateless coding scheme by using a heuristic method. Simulation results show that, compared with existing LT and Raptor codes, the proposed coding scheme has an outperform improvement of throughput.

关键词： Space information networks dying channel outage capacity rateless coding degree distribution

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Using Overhearing and rateless coding in Disseminating Various Messages in Vehicular AdHoc Networks

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IEEE ACCESS 2021年 9卷 125052-125064页

作者： Nozari, Mostafa Hendessi, Faramarz Khiadani, Nadia H. Kachooei, Maryam Ataei Isfahan Univ Technol Dept Elect & Comp Engn Esfahan *** Iran Arak Univ Technol Dept Elect Engn Arak *** Iran

Vehicular Ad hoc Networks (VANETs) are emerging technologies with the primary purpose of establishing Vehicular communications. Available protocols for data dissemination in VANETs are faced with issues like discontinuous connections, uncertainty about receiving messages, collisions, and latency. In this paper, a new method is presented for the dissemination of advertising and infotainment messages. The proposed method has used store carry and forward (SCF), rateless coding, and a new handshake mechanism to solve discontinuous connections, uncertainty about receiving messages, and collision problems, respectively. In this paper, changing the Road Side Unit (RSU) message over time and its impact on the network is proposed as a new step in evaluating data dissemination methods. Our results showed that if changing the RSU message happened very rapidly, the network performance will almost be eliminated;to address this problem and due to the advertising nature of messages, the use of overhearing has been suggested. To the best of our knowledge, this is the first time that message overhearing has been used in VANET. Extensive and accurate simulations results show that the proposed method for 2, 3, 5, and 10 messages: (i) reduces the overhead of handshake on average 70% 63%, 48%, and 3%, (ii) increases the number of delivered packets on average 5%, 22%, 75%, and 84%, and (iii) increases the range of data dissemination on average 47%, 187%, 661%, and 2962%, respectively. With the mentioned improvements, the proposed method can also significantly reduce the latency of disseminating messages between vehicles.

关键词： Protocols Data dissemination Codes Uncertainty Advertising Delays Data models VANETs data dissemination rateless coding overhearing

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A Partial Compress-and-Forward Strategy for Relay-Assisted Wireless Networks Based on rateless coding

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2024年第1期73卷 1462-1466页

作者： Ding, Weihang Shikh-Bahaei, Mohammad Kings Coll London Dept Engn London WC2R 2LS England

In this work, we propose a novel partial compress-and-forward (PCF) scheme for improving the maximum achievable transmission rate of a diamond relay network with two noisy relays. PCF combines conventional compress-and-forward (CF) and amplify-and-forward (AF) protocols, enabling one relay to operate alternately in the CF or the AF mode, while the other relay works purely in the CF mode. As the direct link from the source to the destination is unavailable, and there is no noiseless relay in the diamond network, messages received from both relays must act as side information for each other and must be decoded jointly. We propose a joint decoder to decode two Luby transform (LT) codes received from both relays corresponding to the same original message. Numerical results show that PCF can achieve significant performance improvements compared to decode-and-forward (DF) and pure CF protocols when at least the channels connected to one of the relays are of high quality.

关键词： Relays Decoding Codes Diamonds Protocols Noise measurement Relay networks Partial compress-and-forward rateless coding relays

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Exploiting rateless coding for Massive Access

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2018年第11期67卷 11253-11257页

作者： Chen, Xiaoming Jia, Rundong Zhejiang Univ Coll Informat Sci & Elect Engn Hangzhou 310027 Zhejiang Peoples R China Nanjing Univ Aeronaut & Astronaut Key Lab Dynam Cognit Syst Electromagnet Spectrum Minist Ind & Informat Technol Nanjing 211106 Jiangsu Peoples R China

In this correspondence paper. we design a massive nonorthog- final multiple access (NOMA) scheme with delay provisioning for cellular internet-of-things. In the context of massive access, the severe interuser interference decreases the quality of the received signal, such that it is a nontrivial task to provide a delay provisioning for heterogeneous wireless services. To solve this challenge, we propose a massive NOMA scheme to meet the delay requirements of a large number of users by exploiting the properties of rateless codes. Especially, we present a power allocation algorithm to minimize the power consumption while achieving delay-constrained massive access. Finally, simulation results validate the effectiveness of the proposed scheme.

关键词： Massive access rateless coding delay provisioning NOMA power allocation

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SPARC: Superposition-Aided rateless coding in Wireless Relay Systems

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2011年第9期60卷 4427-4438页

作者： Wang, Xijun Chen, Wei Cao, Zhigang Tsinghua Univ Dept Elect Engn Beijing 100084 Peoples R China

Energy accumulation and information accumulation are two approaches to exploit multiple transmissions in wireless relay systems. There is a tradeoff between energy accumulation and information accumulation from an outage perspective, in which a packet is successfully received if the channel capacity exceeds the transmission rate. However, how to strike a balance between these two approaches is still unknown. In this paper, we propose a new rateless-coding-based transmission scheme in wireless relay systems, where the relay superposes two rateless-coded packets generated from different codebooks to strike a balance between energy accumulation and information accumulation. We analyze the average end-to-end throughput of the proposed scheme and formulate an optimization problem to find the optimal power allocation ratio. Simulation results will validate our analysis and show that, compared with pure energy accumulation and pure information accumulation, our proposed scheme can achieve substantial throughput gain.

关键词： Cross-layer design rateless coding relay transmission superposition coding

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rateless coding Scheme for Time-Varying Dying Channels

Rateless Coding Scheme for Time-Varying Dying Channels

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International Conference on Wireless Communications and Signal Processing

作者： Yang Wang Jian Jiao Xindong Sui Shaohua Wu Yonghui Li Qinyu Zhang Communication Engineering Research Centre Harbin Institute of Technology Shenzhen Graduate School China School of Electrical and Information on Engineering The University of Sydney NSW Australia

ISBN: (纸本)9781509028610

In spatial information networks (SIN), communication links are suffered by periodic time-varying channel noise because of the periodic motion orbit of the space nodes and planets. Moveover, SIN communications may have a probability to fail at random times, such as severe rain attenuation on Ka-band downlinks, or solar scintillation during the superior/inferior solar conjunction. In this paper, we propose a time-vary dying channel with finite channel-length and Rician fading to model this SIN channels, and the upper and lower bounds of outage capacity are derived. Furthermore, we propose a sub-optimal distribution rateless coding scheme by using a heuristic method. Simulation results show that, compared with existing LT and Raptor codes, the proposed coding scheme has an outperform improvement of throughput.

关键词： Space information networks Dying channel Outage capacity rateless coding Degree distribution

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