• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.1
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• pp.147-155
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• 2012

Fountain codes ensure reliability and robustness for time varying channels in wireless communication. In this paper, the concatenated fountain codes for AWGN and slow fading channels are investigated. Wireless system model, which includes the concatenated fountain code and modulation, is proposed. Maximum achievable rate is used for analyzing the performance of the system model for AWGN and fading channels. Belief Propagation (BP) algorithm is used for exploiting the soft information received at the decoder. Simulation results show that, concatenated fountain codes performs significantly better than that of a conventional Fountain codes with large packet lengths for higher Signal to Noise Ratio (SNR) in slow fading channels.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.6
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• pp.2606-2626
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• 2016

This article investigates the distributed data storage problem in the space information network (SIN) using distributed fountain codes. Since space nodes in the SIN are resource-limited, in order to reduce energy consumption while improving the storage reliability, an efficient distributed storage based on fountain codes and probabilistic broadcasting (DSFPB) strategy is proposed. In the proposed strategy, source packets are disseminated among the entire network according to probabilistic broadcasting (PBcast), and the final degree distribution is close to the desired robust soliton distribution (RSD), this is benefited from the appropriate packets encoding procedure of the proposed strategy. As presented by the analysis and simulations, the total cost of data dissemination is greatly reduced compared with existing representative strategies, while improving the decoding performance.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.4
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• pp.23-28
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• 2013

In this paper, we propose a simple bidirectional transmission protocol using network coding and digital Fountain codes. In particular, in the proposed scheme, two sources use digital Fountain codes to transmit their message to each other with the help of relays. Then, relays use Fountain codes and network coding to forward the source messages to both sources. To evaluate performance of the proposed protocols, we present the average total throughput over Rayleigh fading channels via Various Monte-Carlo simulations. Results show that the proposed protocol outperforms the two-way relaying transmission protocol without using network coding technique at high SNR region.

• Journal of Communications and Networks
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• v.14 no.3
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• pp.267-272
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• 2012

In this paper, we study multi-hop cooperative transmission protocols using fountain codes. The proposed protocols can reduce the end-to-end delay and number of stages compared to those in conventional multi-hop transmission. VariousMonte-Carlo simulations are presented to evaluate and compare performance of the protocols over Rayeigh fading channels.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.39-45
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• 2013

In this paper, we propose a cooperative relaying protocol using Fountain codes for secondary network under interference constraint. In the proposed protocol, a secondary source uses Fountain codes to transmit its message to a secondary destination with help of a secondary relay. The secondary source and relay operate in the underlay model, in which they must adapt their transmit power so that the interference caused at a primary user is lower than an allowable threshold. To evaluate performance of the proposed protocol, we derive the expressions of average number of transmission times over Rayleigh fading channel. Various Monte-Carlo simulations are presented to verify the derivations.

• Journal of Communications and Networks
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• v.15 no.4
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• pp.411-421
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• 2013

Digital fountain codes are record-breaking codes for erasure channels. They have many potential applications in both wired and wireless communications. Most existing digital fountain codes operate over binary fields using an iterative belief-propagation (BP) decoding algorithm. In this paper, we propose a new iterative decoding algorithm for both binary and nonbinary fields. The basic form of our proposed algorithm considers both degree-1 and degree-2 check nodes (instead of only degree-1 check nodes as in the original BP decoding scheme), and has linear complexity. Extensive simulation demonstrates that it outperforms the original BP decoding scheme, especially for a small number of source packets. The enhanced form of the proposed algorithm combines the basic form of the algorithm and a guess-based algorithm to further improve the decoding performance. Simulation results demonstrate that it can provide better decoding performance than the guess-based algorithm with fewer guesses, and can achieve decoding performance close to that of the maximum likelihood decoder at a much lower decoding complexity. Last, we show that our nonbinary scheme has the potential to outperform the binary scheme when choosing suitable degree distributions, and furthermore it is insensitive to the size of the Galois field.

• Journal of Communications and Networks
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• v.12 no.6
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• pp.577-581
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• 2010

We introduce a novel packet retransmission technique which improves the efficiency of automatic retransmission query (ARQ) protocols in the context of satellite broadcast/multicast systems. The proposed coded ARQ technique, similarly to fountain coding, performs transmission of redundant packets, which are made by linear combinations of the packets composing the source block. Differently from fountain codes, the packets for the linear combinations are selected on the basis of the retransmission requests coming from the user terminals. The selection is performed in a way that, at the terminals, the source packets can be recovered iteratively by means of simple back-substitutions. This work aims at providing a simple and efficient alternative to reliable multicast protocols based on erasure correction coding techniques.

• KIISE Transactions on Computing Practices
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• v.21 no.1
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• pp.58-63
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• 2015

In this work, we present a novel fountain code-based hybrid P2P storage system that combines cloud storage with P2P storage. The proposed hybrid storage system minimizes data transmission time while guaranteeing high data retrieval and data privacy. In order to guarantee data privacy and storage efficiency, the user transmits encoded data after performing fountain code-based encoding. Also, the proposed algorithm guarantees the user's data retrieval by storing the data while considering each peer's survival probability. The simulation results show that the proposed algorithm enables fast completion of the upload transmission while satisfying the required data retrieval and supporting the privacy of user data under the system parameters.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.2
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• pp.649-663
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• 2012

We propose a percolation based M2M networking architecture and its data transmission method. The proposed network architecture can be server-free and router-free, which allows us to operate routing efficiently with percolations based on six degrees of separation theory in small world network modeling. The data transmission can be divided into two phases: routing and data transmission phases. In the routing phase, probe packets will be transmitted and forwarded in the network thus multiple paths are selected and performed based on the constriction of the maximum hop number. In the second phase, the information will be encoded, say, with the fountain codes, and transmitted using the paths generated in the first phase. In such a way, an efficient routing and data transmission mechanism can be built, which allow us to construct a low-cost, flexible and ubiquitous network. Such a networking architecture and data transmission can be used in many M2M communications, such as the stub network of internet of things, and deep space networking, and so on.

• Information and Communications Magazine
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• v.24 no.4
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• pp.95-105
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• 2007

최근 들어 다중 사용자 환경에서 효율적인 정보 전송에 관한 연구가 진행되면서 새로운 방식의 채널 부호화 기술들이 탄생하였다. 파운틴 코드는 Erasure 채널로 표현되는 네트워크 상에서 다수에게 전송하는 브로드캐스팅 및 멀티캐스팅에 적합하도록 개발된 채널 부호화 기술로서, 정보를 무한히 많은 양으로 부호화하여 전송하는 것을 특징으로 한다. 이와 같은 방식의 채널 부호화 기술은 최근 몇 년간 이론적인 측면뿐만 아니라 실제 표준화 측면에서도 활발하게 연구되고 있다. 본 논문에서는 파운틴 코드에 대하여 소개하고 실제 개발된 몇 가지 파운틴 코드를 소개한다. 그리고 파운틴 코드의 향후 응용 가능성에 대해서도 논의한다.