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Towards interference-Aware ZigBee Transmissions in Heterogeneous Wireless Networks

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Computers, Materials & Continua 2021年第1期66卷 751-765页

作者： Sangsoon Lim Sanghyun Seo Department of Computer Engineering Sungkyul UniversityAnyangSouth Korea School of Computer Art Chung-ang UniversityAnseongSouth Korea

Cross-technology interference(CTI)from diverse wireless networks such as ZigBee,Bluetooth,and Wi-Fi has become a severe problem in the 2.4 GHz Industrial Scientific and Medical(ISM)band.Especially,low power and lossy networks are vulnerable to the signal interferences from other aggressive wireless networks when they perform low power operations to conserve the energy consumption.This paper presents CoSense,which accurately detects ZigBee signals with a reliable signal correlation scheme in the presence of the CTI.The key concept of CoSense is to reduce false wake-ups of low power listening(LPL)by identifying the pre-defined ZigBee signatures.Our scheme is robust in the coexistence environment of diverse wireless technologies since the signal correlation works well in bad wireless channel conditions.It achieves standard compliance and transparency without any hardware and firmware changes.We have implemented CoSense on the Universal Software Radio Peripheral(USRP)platform to verify its feasibility.The experimental exploration reveals that CoSense significantly reduces the false-positive and false-negative rate under typical setting and the additional overhead is negligible.The results show that our scheme saves much energy by up to 63%in dynamic network interference scenarios where low-power ZigBee transmissions are overwhelmed by strong Wi-Fi signal interferences.

关键词： Heterogeneous wireless networks interference ZigBee detection energy efficiency low-power listening

A Novel Radio Resource Management for interference Mitigation in OFDMA System

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China Communications 2010年第1期7卷 23-29页

作者： Gao Peng Meng Dexiang Song Zhiyuan Tu Guofang Grad Univ Chinese Acad Sci Beijing 100049 Peoples R China China Mobile Grp Design Inst Co Ltd Beijing 100080 Peoples R China

In Orthogonal Frequency Division Multiple Access (OFDMA) systems, such as Long Term Evolution (LTE) and so on, the resources used by each user are orthogonal, and the OFDMA systems performances are mainly affected by the inter-cell interference. Therefore, the inter-cell interference mitigation technology becomes a hotspot. The objective of interference mitigation technologies used in OFDMA systems are to increase cell-edge throughput and average cell throughput. In this paper, the Resource Block Planning (BRBP) based scheme is proposed to mitigate the inter-cell interference and improve the cell-edge throughput. Comparison between the simulation results of BRBP and Round Robin (RR) illustrates that the enhanced performance of BRBP.

关键词： OFDMA inter-cell interference mitigation cell-edge throughput resource block planning scheme

Chip-ejection interference in cutting processes of modern cutting tools

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Science China(Technological Sciences) 1999年第3期42卷 275-281页

作者：师汉民 School of Mechanical Engineering Huazhong University of Science and Technology Wuhan China

Based on the “principle of minimum energy”, the basic characteristics of non-free cutting are studied; the phenomenon and the nature of chip-ejection interference commonly existing in the cutting process of modem cutting tools are explored. A 'synthesis method of elementary cutting tools' is suggested for modeling the cutting process of modem complex cutting tools. The general equation governing the chip-ejection motion is deduced. Real examples of non-free cutting are analyzed and the theoretically predicted results are supported by the experimental data or facts. The sufficient and necessary conditions for eliminating chip-ejection interference and for realizing free cutting are given; the idea and the technical approach of 'the principle of free cutting' are also discussed, and a feasible way for improving or optimizing the cutting performance of modem cutting tools is, therefore, found.

关键词： metal cutting principle of minimum energy chip-ejection interference synthesis method of elementary cutting tools.

Routing metric of interference-aware link quality: an improved ETX in wireless mesh networks

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 61-67页

作者： SHI Wen-xiao WU Dan XU Yin-long WANG Ji-hong College of Communication Engineering Jilin University

This article addresses the problem of route selection in wireless mesh networks （WMNs）. The traditional routing metrics adopt packet delivery ratio （PDR） as a representative metric of wireless link quality assessment. However, PDR measured by the broadcast-based probe method is affected by the size, number and transmission rate of probe packets, which influences the metric accuracy. In this paper, improved expected transmission count （iETX）, a new routing metric of interference-aware link quality, is proposed for WMNs. Dispensing with traditional broadcast-based probing method, the iETX uses regional physical interference model to obtain PDR. Regional physical interference model is built upon the relationship between signal to interference plus noise ratio （SINR） and PDR, which contributes to the improvement of metric accuracy. The iETX comprehensively considers the effects of interference and link quality and minimizes the expected number of packet transmissions required for successful delivery, which helps find a path with minimum interference and high throughput. Simulation shows that the proposed metric can significantly improve the network performance.

关键词： WMNs routing metric link quality interference

Inter-Operator interference Coordination for CoPrimary Spectrum Sharing in UDN

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China Communications 2015年第S1期12卷 104-112页

作者： YU Qiaoling WANG Jiang YANG Xiumei ZHU Yuanping TENG Yong Horneman Kari Shanghai Research Center for Wireless Communications Shanghai Institute of Microsystem and Information Technology (SIMIT) Chinese Academy of Sciences (CAS) Nokia

Co-primary spectrum sharing for multiple operators has been utilized to fully explore the spectrum resources and thus improve the spectrum efficiency. The inter-operator interference(IOI) problem should be seriously considered in order to achieve the mentioned target, especially under the scenario of the ultradense network(UDN) in the fifth generation(5G) wireless systems. To solve this problem, we propose an asymmetrical power levels based soft IOI coordination mechanism. The shared spectrum pool is consisted of three separated parts, where each part can be dynamically adjusted according to the minimal spectrum demand from each operator. Furthermore, different power masks are configured to different parts for each operator. The simulation results show that the proposed mechanism can improve the network spectrum efficiency significantly.

关键词： ultra-dense network inter-operator interference coordination co-primary spectrum sharing

Co-Channel interference Suppression Techniques for Full Duplex Cellular System

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China Communications 2015年第S1期12卷 18-27页

作者： XIN Yongchao MA Meng ZHAO Zijun JIAO Bingli School of Electronics Engineering and Computer Science Peking University

Co-frequency and co-time full duplex(CCFD) is a promising technique for improving spectral efficiency in next generation wireless communication systems. However, for the applications of CCFD in a cellular network, severe co-channel interference is an essential problem. Specifically, there are two significant interferences, i.e., inter-terminal interference(ITI) and inter-cell interference(ICI), which lead to an obvious performance degradation. In this paper, two techniques are proposed for suppressing the ITI and ICI in a CCFD cellular system, respectively. The first technique is obtained by modeling the three-node CCFD system as the Z-channel. After deriving the sum-capacity of the Z-channel, a sum-capacity-achieving scheme based on successive interference cancellation(SIC) is proposed. The second technique is designed by combining the fractional frequency reuse scheme with CCFD. The performance gains of the proposed two techniques in terms of signalto-interference plus noise ratio(SINR) and sumcapacity are analyzed. Simulation results show that the proposed scheme can achieve significant interference suppression performance and higher system capacity, especially for cell edge users.

关键词： co-frequency and co-time full duplex(CCFD) fractional frequency reuse(FFR) successive interference cancellation(SIC) Z-channel

Sponge:An Oversubscription Strategy Supporting Performance interference Management in Cloud

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China Communications 2015年第11期12卷 196-209页

作者： LIU Ying Services Computing Technology and System Lab Cluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and Technology

Resource oversubscription optimizes the utilization of the computing resources. Many well-known virtual machine monitors(VMMs)such as Xen and KVM,adopt this approach to help maximize the yield of the cloud datacenters That is,with proper resource oversubscription strategies,more virtual machines(VMs) can be supported by limited resources. However performance interference among VMs hosting in the same physical machines(PMs) exists in cloud environment,and probably aggravated by resource oversubscription strategies,which aims to put more VMs into the same PM. In this paper,we present a resource oversubscription strategy called Sponge targeting cloud platforms Sponge mitigates the issue of performance interference among the oversubscribed co-hosting VMs. Sponge also provides a VM association strategy for each PM to handle with its besteffort. We performed our evaluation on a virtua datacenter simulated by Xen. Our evaluation results show that Sponge improves the resources utilization and manages to make each VM mee its performance requirement even hosting with other VMs in the same PM.

关键词： resources oversubscription performance interference cloud computing resource management

A study on the interference effects for tidal current power rotors

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Science China(Technological Sciences) 2010年第11期53卷 3094-3101页

作者： Chul-Hee JO Kang-Hee LEE Jin-Young YIM Department of Naval Architecture & Ocean Engineering Inha University

Due to global warming, the need to secure an alternative resource has become more important nationally. With the high tidal range of up to 9.7 m on the west coast of Korea, numerous tidal current projects are being planned and constructed. To extract a significant quantity of power, a tidal current farm with a multi-arrangement is necessary in the ocean. The rotor, which initially converts the energy, is a very important component because it affects the efficiency of the entire system, and its performance is determined by various design variables. The power generation is strongly dependent on the size of the rotor and the incoming flow velocity. However, the interactions between devices also contribute significantly to the total power capacity. Therefore, rotor performance considering the interaction problems needs to be investigated for generating maximum power in a specific field. This paper documents a performance study of devices considering the interference between rotating rotors with axial, transverse and diagonal arrangements.

关键词： TCP (tidal current power) renewable energy interference effect rotor CWC (circulation water channel) CFD (computational fluid dynamics)

Suppression of starch synthase I(SSI) by RNA interference alters starch biosynthesis and amylopectin chain distribution in rice plants subjected to high temperature

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The Crop Journal 2019年第5期7卷 573-586页

作者： Qian Zhao Xiaoxia Du Zhanyu Han Yu Ye Gang Pan Muhammad-Asad-Ullah Asad Qifa Zhou Fangmin Cheng Institute of Crop Science College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058ZhejiangChina Jiangsu Collaborative Innovation Center for Modern Crop Production Nanjing 210095JiangsuChina

Based on known cDNAs of rice starch synthase isoforms,we constructed dsRNA interference vectors for starch synthase I(SSI)to produce transgenic plants containing starch with a moderately high amylose content.We investigated the effect of SSI suppression on grain quality traits,starch biosynthesis,and amylopectin chain distribution in rice plants exposed to two different temperature regimes.The activities and transcripts of BEs,DBEs,and other SS isoforms were further investigated to clarify the effect of SSI suppression on these key enzymes and their specific isoforms under different temperature treatments.Suppression of SSI by RNAi altered grain starch component and amylopectin chain distribution,but it exerted only a slight effect on total starch content(%)and accumulation amount(mg kernel?1)and on starch granule morphology and particle size distribution.Under normal temperature(NT),insignificant differences in kernel weight,chalky kernel proportion,chalky degree,and starch granule morphology between SSI-RNAi line and its wild type(WT)were observed.However,amylose content(AC)level and granule-bound starch synthase(GBSS)activity in rice endosperms were markedly increased by SSI-RNAi suppression.The chalky kernel proportion and chalky degree of SSIRNAi lines were significantly higher than those of WT under high temperature(HT)exposure at filling stage.Inhibition of SSI by RNAi affected amylopectin chain distribution and raised starch gelatinization temperature(GT)in two ways:directly from the SSI deficiency itself and indirectly by reducing BEIIb amounts in an SSI-deficient background.The deficiency of SSI expression led to an alteration in the susceptibility of grain chalkiness occurrence and starch gelatinization temperature to HT exposure,owing to a pleiotropic effect of SSI deficiency on the expression of other genes associated with starch biosynthesis.

关键词： Rice Starch synthase I RNA interference Grain quality Amylopectin High temperature