检索结果-内蒙古大学图书馆

International Workshop on High Mobility Wireless Communications (HMWC)

作者： Chen, Li Yakufu, Yushan Yuan, Xiaojun Sun, Zichao Sun Yat Sen Univ Sch Informat Sci & Technol Guangzhou Guangdong Peoples R China ShanghaiTech Univ Sch Informat Sci & Technol Shanghai Peoples R China

ISBN: (纸本)9781467376280

This paper investigates the iterative decoding for spectrally efficient two-way relay (TWR) communications in which two end nodes exchange information through a relay (R). With the use of physical-layer network coding (PNC), information exchange throughput can be significantly improved as only two orthogonal time slots (TS) are required to realize both the multiple access (MAC) and the broadcast (BC) transmissions. During the MAC stage, transmitted symbols from the end nodes are superimposed at R which decodes the exclusive-or (XOR) information of the two end nodes. However, with a high order modulation, symbol superposition will cause demapping ambiguity. This paper proposes a TWR communication system that employs the bit-interleaved coded modulation (BICM). The iterative decoding, namely, the BICM-ID, is introduced to dissolve the demapping ambiguity. With iterative decoding, the transmitted symbol pair probabilities can be better estimated so that the demapper can provide better coded bit information for the decoder. The proposed work generalizes the iterative demapping-decoding approach for TWR channels. Our simulation results demonstrate significant iterative decoding gains can be achieved with a tendency of approaching the XOR-decoding bound.

关键词： BICM iterative decoding physical-layer network coding spectrum efficiency two-way relay

来源：评论

学校读者我要写书评

暂无评论

An Optimal Transmit Power Allocation for the Two-Way Relay Channel Using physical-layer network coding

An Optimal Transmit Power Allocation for the Two-Way Relay C...

引用

IEEE International Conference on Communications (ICC 2009)

作者： Shin, Wonjae Lee, Namyoon Lim, Jong Bu Shin, Changyong Samsung Elect Co Ltd Samsung Adv Inst Technol Commun Lab Yongin 446712 Gyeonggi Do South Korea

ISBN: (纸本)9781424434367

A two-way relaying system using the physical-layer network coding (PNC) does not cause the spectral loss induced by the half-duplex signaling. Furthermore, when the total power, which is limited, is properly distributed to transmission nodes in such a system, the system capacity will be enhanced significantly. In this paper, we propose an optimal power allocation in the two-way relay channel employing the PNC protocol. The optimal power allocation is obtained by maximizing the achievable sum-rate of the PNC protocol under a sum-power constraint in a Rayleigh fading channel environment. Numerical experimental results confirm that the proposed power allocation scheme achieves much higher achievable sum-rate performance than the existing schemes.

关键词： Optimal Power Allocation physical-layer network coding Two-Way Relay Channel

来源：评论

学校读者我要写书评

暂无评论

Wireless MIMO Switching with Trusted and Untrusted Relays: Degrees of Freedom Perspective

Wireless MIMO Switching with Trusted and Untrusted Relays: D...

引用

IEEE International Conference on Communications

作者： Fanggang Wang Xiaojun Yuan Jemin Lee Tony Q. S. Quek State Key Lab of Rail Traffic Control and Safety Beijing Jiaotong University School of Information Science and Technology ShanghaiTech University Singapore University of Technology and Design

ISBN: (纸本)9781467364300

We investigate the degrees of freedom (DoF) and secrecy DoF for a general framework of multiway relay networks named wireless MIMO switching, where a number of users exchange information via a common relay. Each round of data exchange consists of one uplink transmission from users to relay and one downlink transmission from relay back to users. The data exchange model is unicast, i.e., every user transmits one message and intends to receive one message from one other user. We categorize unicast patterns using the notion of orbit borrowed from abstract algebra. Roughly speaking, an orbit is a minimum subset of users such that data exchange is closed within this subset. We analyze the achievable DoF of wireless MIMO switching with various numbers of orbits. Particularly, the DoF capacity for unicast with one and two orbits are established. Furthermore, we study communication secrecy with an untrusted relay in wireless MIMO switching. We present an achievable secrecy sum rate and the corresponding achievable secrecy DoF by assuming a non-regenerative relay. Then, we focus on unicast patterns with one and two orbits, and show that this achievable lower bound is actually the secrecy DoF capacity based on a novel genie-aided technique. Our results build a bridge between the DoF and the secrecy DoF in multiway relaying. The methodology of the proof can be generally applied to analyze the secrecy DoF in other relay networks.

关键词： Degrees of freedom MIMO switching physical-layer network coding Multiway relay Secrecy sum rate

来源：评论

学校读者我要写书评

暂无评论

A Comparative Analysis of Secrecy Rates of Wireless Two-Way Relay Systems

A Comparative Analysis of Secrecy Rates of Wireless Two-Way ...

引用

IEEE Global Communications Conference

作者： Chih-Hua Chang Ronald Y. Chang Yu-Chih Huang School of Electrical and Computer Engineering Purdue University Research Center for Information Technology Innovation Academia Sinica Department of Communication Engineering National Taipei University

ISBN: (纸本)9781479959532

This paper studies the information-theoretic secrecy rates of wireless two-way relay systems where two users wish to exchange information through a single relay with an eavesdropper observing all communications. We formulate and compare the achievable secrecy rates of the system that employs one of the three common relay protocols: conventional decode-and-forward (DF), DF with network coding (NC), and compute-and-forward (CF) based on physical-layer network coding (PNC). We show that CF based on PNC achieves the highest secrecy rate at high signal-to-noise ratio (SNR), while, interestingly, the other two protocols have mixed performance depending on the power allocation scheme and network topology. Our study offers insights into designing wireless two-way relay protocols from a secrecy perspective.

关键词： Two-way relaying Information-theoretic security physical-layer security network coding physical-layer network coding network coding Relay systems Privacy Bidirectional physical layer PNC signal to noise ratios wireless computer information security power splitting relay

来源：评论

学校读者我要写书评

暂无评论

network-Coded Multiple Access

引用

IEEE TRANSACTIONS ON MOBILE COMPUTING 2014年第12期13卷 2853-2869页

作者： Lu, Lu You, Lizhao Liew, Soung Chang Chinese Univ Hong Kong Inst Network Coding Hong Kong Hong Kong Peoples R China Chinese Univ Hong Kong Dept Informat Engn Hong Kong Hong Kong Peoples R China

This paper proposes and experimentally demonstrates a first wireless local area network (WLAN) system that jointly exploits physical-layer network coding (PNC) and multiuser decoding (MUD) to boost system throughput. We refer to this multiple access mode as network-coded multiple access (NCMA). Prior studies on PNC mostly focused on relay networks. NCMA is the first realized multiple access scheme that establishes the usefulness of PNC in a non-relay setting. NCMA allows multiple nodes to transmit simultaneously to the access point (AP) to boost throughput. In the non-relay setting, when two nodes A and B transmit to the AP simultaneously, the AP aims to obtain both packet A and packet B rather than their network-coded packet. An interesting question is whether network coding, specifically PNC which extracts packet A circle plus B, can still be useful in such a setting. We provide an affirmative answer to this question with a novel two-layer decoding approach amenable to real-time implementation. Our USRP prototype indicates that NCMA can boost throughput by 100 percent in the medium-high SNR regime (>= 10 dB). We believe further throughput enhancement is possible by allowing more than two users to transmit together.

关键词： network coding physical-layer network coding multi-user detection multiple access implementation

来源：评论

学校读者我要写书评

暂无评论

Achievable Rate Regions for Two-Way Relay Channel Using Nested Lattice coding

引用

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2014年第10期13卷 5607-5620页

作者： Smirani, Sinda Kamoun, Mohamed Sarkiss, Mireille Zaidi, Abdellatif Duhamel, Pierre CEA LIST Commun Syst Lab F-91191 Gif Sur Yvette France Univ Paris Est Marne la Vallee LIGM F-77454 Marne La Vallee 2 France Supelec CNRS LSS F-91192 Gif Sur Yvette France

This paper studies a Gaussian two-way relay channel where two communication nodes exchange messages with each other via a relay. It is assumed that all nodes operate in half-duplex mode without any direct link between the communication nodes. A compress-and-forward relaying strategy using nested lattice codes is first proposed. Then, the proposed scheme is improved by performing layered coding: A common layer is decoded by both receivers, and a refinement layer is recovered only by the receiver that has the best channel conditions. The achievable rates of the new scheme are characterized and are shown to be higher than those provided by the decode-and-forward strategy in some regions.

关键词： Compress-and-forward Gaussian channel lattice codes physical-layer network coding side information two-way relay channel

来源：评论

学校读者我要写书评

暂无评论

Detection of Intelligent Malicious User in Cognitive Radio network by Using Friend or Foe (FoF) Detection Technique

Detection of Intelligent Malicious User in Cognitive Radio N...

引用

International Telecommunication networks and Applications Conference

作者： Saifur Rahman Sabuj Masanori Hamamura Shougo Kuwamura Graduate School of Engineering Kochi University of Technology

ISBN: (纸本)9781467393492

In a cognitive radio network, dynamic spectrum must be shared with an unlicensed user because of the limited bandwidth of the wireless spectrum. As a regulation of cognitive radio networks, a secondary user is allowed to utilize the unoccupied spectrum when it is not being used by the primary user. However, an intelligent malicious user can attack a cognitive radio network and block the permitted channel for the secondary user. The invasion of an intelligent malicious user is a serious problem in the deployment of such networks. In this paper, we introduce a novel scheme based on friend or foe (FoF) detection with physical-layer network coding to detect a secondary user and an intelligent malicious user. The entire cognitive radio network is protected while the secondary user and intelligent malicious user are accurately detected. The effectiveness of the proposed approach is analyzed theoretically and by MATLAB simulation. It is shown that with the FoF detection technique and the proposed algorithm, the base station can detect the secondary user and intelligent malicious user with high accuracy. Computer simulations show that the probability of detection is almost 100% and that the probability of the false alarm is almost 0% for a low E_b/N_0. Consequently, the proposed technique can be applied to a cognitive radio network to protect the entire network and ensure appropriate channel utilization by the secondary user.

关键词： Cognitive radio network Friend or foe detection physical-layer network coding Cross-correlation

来源：评论

学校读者我要写书评

暂无评论

MIMO Multiway Relaying With Clustered Full Data Exchange: Signal Space Alignment and Degrees of Freedom

引用

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2014年第12期13卷 6795-6808页

作者： Yuan, Xiaojun ShanghaiTech Univ Sch Informat Sci & Technol Shanghai 200031 Peoples R China

Recently, much research interest has been focused on the design of efficient communication mechanisms for multiple-input-multiple-output (MIMO) multiway relay channels (mRCs). In this paper, we investigate achievable degrees of freedom (DoFs) of the MIMO mRC with L clusters and K users per cluster, where each user is equipped with M antennas and the relay with N antennas. Our analysis is focused on a new data exchange model, termed clustered full data exchange, i.e., each user in a cluster wants to learn the messages of all the other users in the same cluster. Novel signal alignment techniques are developed to jointly and systematically construct the beamforming matrices at the users and the relay for efficient implementation of physical-layer network coding. Based on this, we derive an achievable DoF of the MIMO mRC with an arbitrary network configuration of L and K, as well as with an arbitrary antenna configuration of M and N. We show that our proposed scheme achieves the DoF capacity when M/N <= 1/(LK - 1) and M/N >= ((K - 1) L + 1)/KL. The DoF results derived in this paper can serve as fundamental benchmarks in evaluating the performance of practical communication systems over MIMO mRCs and provide guidance and insights into the design of wireless relay networks.

关键词： Multiway relay channels degrees of freedom multiple-input multiple-output systems physical-layer network coding signal and interference alignment

来源：评论

学校读者我要写书评

暂无评论

Generalized Low-Density (GLD) Lattices

Generalized Low-Density (GLD) Lattices

引用

IEEE Information Theory Workshop (ITW)

作者： Boutros, Joseph J. di Pietro, Nicola Basha, Nour Texas A&M Univ Qatar Doha 23874 Qatar

ISBN: (纸本)9781479959990

We propose the construction of a new family of lattice sphere packings. Given a small-dimensional lattice, we start by building a first lattice in a large dimension by the direct sum of the small lattice. Then, the coordinates of the first large lattice are permuted to yield a second large-dimensional lattice. Finally, our generalized low-density (GLD) lattice is the intersection of the first and the second lattice. We restrict our construction in this paper to integer lattices. GLD lattices are the result of mixing classical lattice theory with modern coding theory. They are potential candidates not only for channel coding as coded modulations, but also for physical-layer network coding and for secure digital communications.

关键词： channel coding network coding coded modulations coding theory generalized low-density lattices large-dimensional lattice lattice sphere packings lattice theory physical-layer network coding secure digital communications small-dimensional lattice Channel coding Constellation diagram Generators Iterative decoding Lattices Maximum likelihood decoding Zinc Channel coding crystal lattices lattice theory Shannon's theory Constellation diagram maximum likelihood decoding Iterative decoding network coding dynamos zinc New families

来源：评论

学校读者我要写书评

暂无评论

Transmission Protocol Design for Binary physical network Coded Multi-Way Relay networks 79

Transmission Protocol Design for Binary Physical Network Cod...

引用

IEEE 79th Vehicular Technology Conference (VTC-Spring)

作者： Chang, Ronald Y. Lin, Sian-Jheng Chung, Wei-Ho Acad Sinica Res Ctr Informat Technol Innovat Taipei Taiwan

ISBN: (纸本)9781479944828

This paper considers a multi-way relay network in which multiple users intend to achieve full information exchange with one another with the aid of a single relay. A general method for designing the transmission protocol with binary physical-layer network coding (PNC) is developed based on a tree representation. Different transmission schemes are analytically and numerically examined in terms of the decoding strategy, throughput performance, and energy consumption. It is shown that distributing the load of transmissions unevenly among users may achieve a better network throughput performance although some users will consume remarkably more energy than others. A systematic approach to designing the transmission scheme such that minimum error probability is achieved while some specified energy constraint is satisfied is also proposed.

关键词： physical-layer network coding denoise-and-forward multi-way relaying communication protocol tree representation

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：