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Design Method for Optimizing the Interactive Interface of Live Broadcasting Platform for the Elderly Users
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作者 WEI Bi-ze FAN Wei DUAN Ying-ke 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期167-178,共12页
In the era of network live broadcasting for everyone,the development of live broadcasting platforms is also more intelligent and diversified.However,in the face of a large group of elderly users,the interface interact... In the era of network live broadcasting for everyone,the development of live broadcasting platforms is also more intelligent and diversified.However,in the face of a large group of elderly users,the interface interaction design mode used is still mainly based on the interaction mode for young groups,and is not designed for elderly users.Therefore,a design method for optimizing the interaction interface of live broadcasting platform for elderly users was proposed in this study.Firstly,the case study method and Delphi expert survey method were used to determine the design needs of elderly users and the design mode was analysed.Secondly,the orthogonal design principle was used to design a test sample of the interactive interface of live broadcasting platform applicable for the elderly users,and then a user evaluation system was established to calculate the weights of the design elements using hierarchical analysis,and then the predictive relationship between the design mode of the interactive interface of live broadcasting platform and the elderly users was established by Quantitative Theory I.Finally,Genetic Algorithm was applied to generate the optimized design scheme.The results showed that the design method based on the Genetic Algorithm and the combination of Quantitative Theory can scientifically and effectively optimize the design of the interactive interface of the live broadcasting platform for the elderly users,and improve the experience of the elderly users. 展开更多
关键词 Live broadcasting platform Interaction design Elderly users Genetic Algorithm Quantitative Theory I
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Cooperative Covert Communication in Multi-Antenna Broadcast Channels
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作者 Qiao Sen Liu Guangjie +1 位作者 Ji Xiaopeng Liu Weiwei 《China Communications》 SCIE CSCD 2024年第6期246-260,共15页
With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two... With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two-user cooperative multi-antenna broadcast channel.We focus on the issue that the deteriorated reliability and undetectability are mainly affected by the transmission power.To tackle this issue,we design a scheme based on beamforming to increase the reliability and undetectability of wireless covert communication in the multi-antenna broadcast channel.We first modeled and analyzed the cooperative multi-antenna broadcasting system,and put forward the target question.Then we use the SCA(successive convex approximation)algorithm to transform the target problem into a series of convex subproblems.Then the convex problems are solved and the covert channel capacity is calculated.In order to verify the effectiveness of the scheme,we conducted simulation verification.The simulation results show that the proposed beamforming scheme can effectively improve the reliability and undetectability of covert communication in multi-antenna broadcast channels. 展开更多
关键词 BEAMFORMING covert communication multi-antenna broadcast channels OFDM
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Multi-User Semantic Fusion for Semantic Communications over Degraded Broadcast Channels
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作者 Wu Tong Chen Zhiyong +2 位作者 Tao Meixia Xia Bin Zhang Wenjun 《China Communications》 SCIE CSCD 2024年第10期86-100,共15页
Degraded broadcast channels(DBC) are a typical multiuser communication scenario, Semantic communications over DBC still lack in-depth research. In this paper, we design a semantic communications approach based on mult... Degraded broadcast channels(DBC) are a typical multiuser communication scenario, Semantic communications over DBC still lack in-depth research. In this paper, we design a semantic communications approach based on multi-user semantic fusion for wireless image transmission over DBC. The transmitter extracts semantic features for two users separately and then effectively fuses them for broadcasting by leveraging semantic similarity. Unlike traditional allocation of time, power, or bandwidth, the semantic fusion scheme can dynamically control the weight of the semantic features of the two users to balance their performance. Considering the different channel state information(CSI) of both users over DBC,a DBC-Aware method is developed that embeds the CSI of both users into the joint source-channel coding encoder and fusion module to adapt to the channel.Experimental results show that the proposed system outperforms the traditional broadcasting schemes. 展开更多
关键词 channel adaptability degraded broadcasting channels semantic communications semantic fusion
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A Deep Learning Based Broadcast Approach for Image Semantic Communication over Fading Channels
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作者 Ma Kangning Shi Yuxuan +1 位作者 Shao Shuo Tao Meixia 《China Communications》 SCIE CSCD 2024年第7期78-94,共17页
We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adapt... We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adaptive semantic transmission in terms of different channel states.We combine the classic broadcast approach with the image transformer to implement this adaptive joint source and channel coding(JSCC)scheme.Specifically,we utilize the neural network(NN)to jointly optimize the hierarchical image compression and superposition code mapping within this scheme.The learned transformers and codebooks allow recovering of the image with an adaptive quality and low error rate at the receiver side,in each channel state.The simulation results exhibit our proposed scheme can dynamically adapt the coding to the current channel state and outperform some existing intelligent schemes with the fixed coding block. 展开更多
关键词 broadcast approach deep learning fading channels semantic communication
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Wireless location algorithm using digital broadcasting signals based on neural network 被引量:1
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作者 柯炜 吴乐南 殷奎喜 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期394-398,共5页
In order to enhance the accuracy and reliability of wireless location under non-line-of-sight (NLOS) environments,a novel neural network (NN) location approach using the digital broadcasting signals is presented. ... In order to enhance the accuracy and reliability of wireless location under non-line-of-sight (NLOS) environments,a novel neural network (NN) location approach using the digital broadcasting signals is presented. By the learning ability of the NN and the closely approximate unknown function to any degree of desired accuracy,the input-output mapping relationship between coordinates and the measurement data of time of arrival (TOA) and time difference of arrival (TDOA) is established. A real-time learning algorithm based on the extended Kalman filter (EKF) is used to train the multilayer perceptron (MLP) network by treating the linkweights of a network as the states of the nonlinear dynamic system. Since the EKF-based learning algorithm approximately gives the minimum variance estimate of the linkweights,the convergence is improved in comparison with the backwards error propagation (BP) algorithm. Numerical results illustrate thatthe proposedalgorithmcanachieve enhanced accuracy,and the performance ofthe algorithmis betterthanthat of the BP-based NN algorithm and the least squares (LS) algorithm in the NLOS environments. Moreover,this location method does not depend on a particular distribution of the NLOS error and does not need line-of-sight ( LOS ) or NLOS identification. 展开更多
关键词 digital broadcasting signals neural network extended Kalman filter (EKF) backwards error propagation algorithm multilayer perceptron
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Broadcasting with Controlled Redundancy and Improved Localization in Wireless Sensor Networks 被引量:2
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作者 Tarun Dubey Om Prakash Sahu 《Journal of Electronic Science and Technology》 CAS 2013年第4期404-407,共4页
Wireless sensor networks (WSNs) consist of sensor nodes that broadcast a message within a network. Efficient broadcasting is a key requirement in sensor networks and has been a focal point of research over the last ... Wireless sensor networks (WSNs) consist of sensor nodes that broadcast a message within a network. Efficient broadcasting is a key requirement in sensor networks and has been a focal point of research over the last few years. There are many challenging tasks in the network, including redundancy control and sensor node localization that mainly depend on broadcasting. In this paper, we propose a broadcasting algorithm to control redundancy and improve localization (BACRIL) in WSNs. The proposed algorithm incorporates the benefits of the gossip protocol for optimizing message broadcasting within the network. Simulation results show a controlled level of redundancy, which is up to 57.6% if the number of sensor nodes deployed in a 500 m×500 m area are increased from 50 to 500. 展开更多
关键词 broadcast GOSSIP LOCALIZATION nodedensity REDUNDANCY wireless sensor networks.
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Partially secret broadcasting,partially secret splitting with quantum entanglement 被引量:2
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作者 刘玉 张彬彬 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期90-94,共5页
In this paper, we propose a classical secret broadcasting and splitting joint protocol in a quantum scenario. With those genuinely entangled states, the boss can always broadcast some of his secrets and split some oth... In this paper, we propose a classical secret broadcasting and splitting joint protocol in a quantum scenario. With those genuinely entangled states, the boss can always broadcast some of his secrets and split some others to multi- receivers at the same time. The efficiency of the joint protocol is also compared with that of two separate ones which realise classical secret broadcasting and classical secret splitting respectively, and based on the comparison we can see the promising advantage of our joint protocol is that it can realise the two tasks more efficiently and more conveniently. 展开更多
关键词 secret broadcasting secret splitting quantum entanglement
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Impact of small-world topologies on broadcasting for wireless sensor networks 被引量:2
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作者 Jiang Nan Yang Shuqun +1 位作者 Zhou Liang Ding Qiulin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第1期192-196,共5页
Broadcasting is an important operation and been widely used in wireless sensor networks (WSNs). These networks are power constrained as nodes operate with limited battery power. Wireless sensor networks are spatial ... Broadcasting is an important operation and been widely used in wireless sensor networks (WSNs). These networks are power constrained as nodes operate with limited battery power. Wireless sensor networks are spatial graphs that have much more clustered and much high path-length characteristics. After considering energy- efficient broadcasting in such networks, by combining the small-world characteristic of WSNs and the properties of ant algorithm to quickly identify an optimal path, small-world power-aware broadcast algorithm is introduced and evaluated. Given different densities of network, simulation results show that our algorithm significantly improves life of networks and also reduces communication distances and power consumption. 展开更多
关键词 small world ant colony algorithm broadcasting wireless sensor networks.
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A Preamble-Based Broadcasting Technique for Wireless Ad Hoc Sensor Networks 被引量:1
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作者 Arun Kumar Kai-Juan Wong 《Communications and Network》 2011年第2期73-84,共12页
Broadcasting is a fundamental operation in any wireless networks, more so in wireless ad hoc sensor networks, where each sensor node has limited transmission range as well as battery power. Although broadcasting in wi... Broadcasting is a fundamental operation in any wireless networks, more so in wireless ad hoc sensor networks, where each sensor node has limited transmission range as well as battery power. Although broadcasting in wireless ad hoc sensor networks has many advantages but it can cause serious problems like-broadcast storm, which could cause a lot of contention, redundant retransmission, collision and most importantly, drain immense amount of energy from limited battery powered sensor nodes. In this work, our objective is to reduce the number of retransmission and energy consumption of sensor nodes by using the duty cycle property of wireless ad hoc sensor networks. We propose a preamble-based broadcasting technique for wireless ad hoc sensor networks. We show that in dense wireless ad hoc sensor networks a small size preamble can give maximum network-wide data dissemination rather than using the large preamble, which will only consume immense amount of energy during packet reception. 展开更多
关键词 broadcast FLOODING Wireless AD HOC Sensor Network.
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A smartcard conditional access interface scheme for conditional access subsystem separation in digital TV broadcasting 被引量:2
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作者 XIE Qiang ZHENG Shi-bao YU Xiao-jing 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期1008-1017,共10页
Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits.... Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry. 展开更多
关键词 Digital TV broadcasting Conditional access subsystem separation Smartcard interface
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DIFFERENTIAL AMPLITUDE PHASE SHIFT KEYING: A NEW MODULATION METHOD FOR TURBO CODE IN DIGITAL RADIO BROADCASTING 被引量:2
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作者 Khalid H. Sayhood Wu Lenan (Radio Engineering Department, Southeast University, Nanjing 210096) 《Journal of Electronics(China)》 2003年第2期86-96,共11页
The multilevel modulation techniques nf M-Differential Amplitude Phase Shift Keying (DAPSK) have been proposed in combination with Turbo code scheme for digital radio broadcasting bands below 30 MHz radio channel. Com... The multilevel modulation techniques nf M-Differential Amplitude Phase Shift Keying (DAPSK) have been proposed in combination with Turbo code scheme for digital radio broadcasting bands below 30 MHz radio channel. Comparison of this modulation method with channel coding in an Additive White Gaussian Noise (AWGN) and multi-path fading channels has been presented. The analysis provides an iterative decoding of the Turbo code. 展开更多
关键词 DAPSK system Turbo code Digital radio broadcasting
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High Robust Broadcasting over DTMB-A with Low-rate LDPC Codes 被引量:2
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作者 Chao Zhang Kewu Peng +2 位作者 Zhitong He Yonglin Xue Hui Yang 《China Communications》 SCIE CSCD 2022年第3期192-201,共10页
As the 2nd generation digital terrestrial television broadcasting(DTTB)standard,digital terrestrial/television multimedia broadcasting-advanced(DTMB-A)can provide higher spectrum efficiency and transmission reliabilit... As the 2nd generation digital terrestrial television broadcasting(DTTB)standard,digital terrestrial/television multimedia broadcasting-advanced(DTMB-A)can provide higher spectrum efficiency and transmission reliability by adopting flexible frame structure and advanced forward error correction coding compared with the 1 st generation DTTB systems.In order to increase the flexibility and robustness of the DTTB network,the frequency reuse scheme of factor one(reuse-1)is proposed,where the same RF channel is used by different stations covering the adjacent service areas.However,it demands a very low carrier-tonoise ratio(C/N)threshold below 0 dB at the DTTB physical layer.In this paper,a robust broadcasting technique is proposed based on DTMB-A with newly designed low-rate low density parity check(LDPC)codes.By adopting quasi-cyclic(QC)Raptor-like structure and progressive lifting method,the high performance low-rate LDPC codes are designed supporting multiple code lengths.Both density-evolution analyses and laboratory measurements demonstrate that DTMB-A with low-rate coding can complete the demodulation reliably with the C/N threshold below0 d B,which is one important necessary condition to support frequency reuse-1 scheme. 展开更多
关键词 digital terrestrial/television multimedia broadcasting-advanced(DTMB-A) digital terrestrial television broadcasting(DTTB) low-rate low density parity check(LDPC)code
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Performance Evaluation of Pipelining Broadcasting in Multicomputer System
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作者 刘宏伟 李晓明 崔光佐 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第2期43-48,共6页
Communication overhead is an important factor in massively parallel processing systems and it has a dramatic influence on the performance of systems. If it can be implemented as quickly as possible, then the performan... Communication overhead is an important factor in massively parallel processing systems and it has a dramatic influence on the performance of systems. If it can be implemented as quickly as possible, then the performance of systems can be greatly improved. Based on the TORUS interconnection network, this paper presents the pipelining broadcasting, which reduces the broadcasting delay and improve the performance of systems. 展开更多
关键词 broadcast PIPELINE MULTICOMPUTER TORUS network
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The Adaptive Long-Distance HF Broadcasting System Based on Backscatter Technique
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作者 Guan Rongsheng Jin Qi Xie Shuguo 《Wuhan University Journal of Natural Sciences》 CAS 1998年第2期165-168,共4页
We put forth a project, that is: using the backscatter technique to realize adaptive long-distance HF broadcasting system in order to improve the quality of HF broadcasting. Then, we analyze errors of the system due t... We put forth a project, that is: using the backscatter technique to realize adaptive long-distance HF broadcasting system in order to improve the quality of HF broadcasting. Then, we analyze errors of the system due to the deviation of the ionospheric parameters' prediction. From the analysis, we draw the conclusion that our project is feasible. In addition, we point out that we can use frequency-spreading and information-coding technique to acquire more clear ionograms. We also offer a judgment on how to choose the control propagation mode on condition of multihop and the existence of more than one propagation mode on the signals' path. 展开更多
关键词 HF broadcasting channel backscatter technique frequency-spreading CODING
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Environmental impact of electromagnetic radiation from the 10kWmedium wave transmitter of Weihai Broadcasting Station
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作者 Wen Congjiang Lu Deming +1 位作者 Wang Shuquan,Wang Baosheng Hu Baoge(Department of Physics , Ocean University of Qingdao, Qingdao 266003 , China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第4期461-467,共7页
Environmentalimpactofelectromagneticradiationfromthe10kWmediumwavetransmitterofWeihaiBroadcastingStationWenC... Environmentalimpactofelectromagneticradiationfromthe10kWmediumwavetransmitterofWeihaiBroadcastingStationWenCongjiang;LuDeming... 展开更多
关键词 environmental impact assessment electromagnetic radiation broadcasting station electromagneticpollution.
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The Response Time Analysis of Digital Broadcasting System
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作者 WANGShuo ZHANGJiang-ling FENGDan 《Wuhan University Journal of Natural Sciences》 CAS 2005年第3期515-519,共5页
Digital broadcasting system has become a high-light of research on computer application. To respond to the changes of the playbill in the broadcasting system in real time, the response time of the system must be studi... Digital broadcasting system has become a high-light of research on computer application. To respond to the changes of the playbill in the broadcasting system in real time, the response time of the system must be studied. There is scarcely the research on this area currently. The influence factors in the response time are analyzed; the model on the response time of the system service is built; how the influence factors affect the response time of the system service is validated; and four improvement measures are proposed to minimize the response time of system service. 展开更多
关键词 Key words digital broadcasting system response time ANALYSIS REAL TIME
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Scheduling for constantly-evolving data broadcasting in asymmetric communication networks
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作者 许华杰 李国徽 《Journal of Shanghai University(English Edition)》 CAS 2008年第6期508-514,共7页
Recent advances in wireless sensor networks and GPS have made constantly-evolving data a new type of data which bring a new challenge to traditional data processing methods. Data broadcasting is an effective means for... Recent advances in wireless sensor networks and GPS have made constantly-evolving data a new type of data which bring a new challenge to traditional data processing methods. Data broadcasting is an effective means for data dissemination in asymmetric communication networks, such as wireless networks. In this paper, definition of the mean uncertainty ratio of data is presented and a broadcasting scheme is proposed for constantly-evolving data dissemination. Simulation results show that the scheme can reduce the uncertainty of the broadcasted constantly-evolving data effectively at the cost of minor increase in data access time, in the case of no transmission error, transmission errors present, and multiple broadcast channels. As a result it benefits the qualities of the query results based on the data. 展开更多
关键词 symmetric communication networks constantly-evolving data broadcasting SCHEDULING
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Forwarding vs. Network Coding: Efficient Broadcasting in Multihop Wireless Networks
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作者 Suranjit Paul Thomas Kunz Li Li 《International Journal of Communications, Network and System Sciences》 2011年第4期205-218,共14页
Broadcasting is used as a building block in many MANET (Mobile Ad hoc Network) routing protocols. In addition, broadcasting is a key primitive in ad hoc networks to support group-based applications. Efficiently suppor... Broadcasting is used as a building block in many MANET (Mobile Ad hoc Network) routing protocols. In addition, broadcasting is a key primitive in ad hoc networks to support group-based applications. Efficiently supporting broadcasting in multihop wireless networks is therefore important. In this paper, we compare ef-ficient broadcasting protocols based on packet forwarding with those based on network coding. Using a number of network scenarios, we derive lower bounds for the required number of packet retransmissions at the MAC layer to support broadcast with and without applying network coding techniques. We compare these lower bounds with each other, as well as with protocols proposed for each approach. More specifically, we use SMF and PDP as sample forwarding-based broadcast protocols, and a simple XOR-based coding protocol over SMF and PDP as representative network coding solution. The results show that neither packet forwarding protocols nor network coding protocols achieve the theoretical lower bounds, in particular as the size of the network area (at constant density) increases. The comparison of the lower bounds also shows that network coding does have a potential performance advantage over packet forwarding solutions for broad-casting in multi-hop wireless networks, in particular for larger fixed density networks, justifying its inherent increased complexity. 展开更多
关键词 MANETS broadcasting MULTI-HOP Networks SMF PDP Network Coding
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Improved Self-Pruning for Broadcasting in Ad Hoc Wireless Networks
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作者 Raqeebir Rab Shaheed Ahmed Dewan Sagar +3 位作者 Nazmus Sakib Ahasanul Haque Majedul Islam Ashikur Rahman 《Wireless Sensor Network》 2017年第2期73-86,共14页
Reducing number of forwarding nodes is the main focus of any broadcasting algorithm designed for ad-hoc wireless networks. All reliable broadcasting techniques can be broadly classified under proactive and reactive ap... Reducing number of forwarding nodes is the main focus of any broadcasting algorithm designed for ad-hoc wireless networks. All reliable broadcasting techniques can be broadly classified under proactive and reactive approaches. In proactive approach, a node selects a subset of its neighbors as forwarding node and announces the forwarding node list in the packet header during broadcast. On the other hand, no such forwarding list is generated in reactive approach. Rather, a node (cognitively) determines by itself whether to forward the packet or not based on neighbor information. Dominant pruning and Self-pruning are two example techniques that fall under proactive and reactive approach respectively. Between the two methods, dominant pruning shows better performance than self-pruning in reducing number of forwarding nodes as they work with extended neighbor knowledge. However, appended forwarding node list increases message overhead and consumes more bandwidth. As a result, the approach becomes non-scalable in large networks. In this paper, we propose a reactive broadcasting technique based on self-pruning. The proposed approach dubbed as “Improved Self-pruning based Broadcasting (ISB)” algorithm completes the broadcast with smaller packet header (i.e., with no overhead) but uses extended neighbor knowledge. Simulation results show that ISB outperforms dominant pruning and self-pruning. Furthermore, as the network gets more spread and denser, ISB works remarkably well. 展开更多
关键词 broadcasting PRUNING FORWARDING Set HEURISTICS
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An Analytical Study of Variable Preamble Length-Based Broadcasting Scheme for WSNs
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作者 Arun Kumar Kai-Juan Wong 《Communications and Network》 2013年第3期517-523,共7页
In this paper, we present a detailed analytical study of previously proposed variable preamble length-based broadcasting scheme for wireless sensor networks (WSNs). Analytical results show that in dense wireless senso... In this paper, we present a detailed analytical study of previously proposed variable preamble length-based broadcasting scheme for wireless sensor networks (WSNs). Analytical results show that in dense wireless sensor networks, broadcasting a packet with a small size preamble can significantly improve the energy conservation on already limited battery powered sensor nodes. For fairer comparison with variable preamble length-based broadcasting scheme, a comprehensive analytical study for an existing probability-based broadcasting scheme is also presented. Analytically calculated results show that variable preamble length-based broadcasting scheme is more energy-efficient than the probability-based broadcasting scheme. 展开更多
关键词 broadcast FLOODING ANALYTICAL Model Wireless Sensor Network
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