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China Communications 2015年第7期12卷 142-153页

作者： SHAO Sujie GUO Shaoyong QIU Xuesong MENG Luoming LEI Min State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Information Security Center Beijing University of Posts and Telecommunications Beijing 100876 China National Engineering Laboratory for Disaster Backup and Recovery Beijing 100876 China Nanjing University of Information Science & Technology (NUIST) Nanjing 210044 China

Meter Data Collection Building Area Network(MDCBAN) deployed in high rises is playing an increasingly important role in wireless multi-hop smart grid meter data collection. Recently, increasingly numerous application layer data traffic makes MDCBAN be facing serious communication pressure. In addition, large density of meter data collection devices scattered in the limited geographical space of high rises results in obvious communication interference. To solve these problems, a traffic scheduling mechanism based on interference avoidance for meter data collection in MDCBAN is proposed. Firstly, the characteristics of network topology are analyzed and the corresponding traffic distribution model is proposed. Next, a wireless multi-channel selection scheme for different Floor Gateways and a single-channel time unit assignment scheme for data collection devices in the same Floor Network are proposed to avoid interference. At last, a data balanced traffic scheduling algorithm is proposed. Simulation results show that balanced traffic distribution and highly efficient and reliable data transmission can be achieved on the basis of effective interference avoidance between data collection devices.

关键词： smart grid communication meter data collection traffic scheduling interference avoidance building area network

Novel scheme for interference avoidance in cognitive radio based cellular networks

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 69-76页

作者： WANG Sai XU Xiao-dong CHEN Xin TAO Xiao-feng WANG Qiang Wireless Technology Innovation Institute Key Laboratory of Universal Wireless CommunicationMinistry of Education Beijing University of Posts and TelecommunicationsBeijing 100876China.

The cognitive radio （CR） technology is believed to improve the spectrum efficiency. However, the interference problem has become a critical issue due to the coexistence of primary systems and CR systems. In this paper, the interferences in CR based cellular networks are discussed. interference scenarios are analyzed, considering different interference sources. Meanwhile, an improved model named ＇Cognitive interference Ring＇ is introduced to describe the interference range of each secondary user （SU）. Depending on the above analysis, graph coloring based dynamic power allocation （GCDPA） scheme is proposed for interference avoidance. Simulation results demonstrate that in CR based cellular networks, the interferences to primary users （PUs） can be effectively mitigated with the proposed GCDPA scheme, and the system throughput and power efficiency are both improved.

关键词： CR interference analysis interference avoidance graph coloring power allocation cellular networks

Price-based interference avoidance game in the Gaussian interference channel

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Science China(Information Sciences) 2012年第2期55卷 301-311页

作者： JING ZhenHai1,BAI BaoMing1 & MA Xiao2 1State Key Laboratory of Integrated Services Networks,Xidian University,Xi'an 710071,China 2Department of Electronics and Communication Engineering,Sun Yat-sen University,Guangzhou 510275,China 1. State Key Laboratory of Integrated Services Networks Xidian University Xi’an 710071 China2. Department of Electronics and Communication Engineering Sun Yat-sen University Guangzhou 510275 China

This paper considers a distributed interference avoidance problem employing frequency assignment in the Gaussian interference channel(IC).We divide the common channel into several sub-channels and each user chooses one sub-channel for transmission in such a way that the total interference in the IC is *** mechanism named interference avoidance in this paper can be modeled as a competitive game *** a completely autonomous distributed iterative algorithm called distributed interference avoidance algorithm(DIA)is adopted to achieve the Nash equilibrium(NE)of the *** to the self-optimum,the DIA is a sub-optimal ***,through introducing an optimal compensation(or price)into the competitive game model,we successfully develop a compensation-based game model to approximate the optimal interference avoidance ***,an optimal algorithm called iterative optimal interference avoidance algorithm(IOIA)is proposed to reach the optimality of the interference avoidance *** analyze the implementation complexity of the proposed algorithm which is only O(N),with N standing for the number of users in the *** also give the proof on the convergence of the proposed *** performance upper bound and lower bound are derived for the IOIA *** simulation results show that the IOIA does reach the optimality under the condition of interference avoidance mechanism.

关键词： interference channel interference avoidance game theory

Co-Frequency interference Analysis and avoidance Between NGSO Constellations: Challenges, Techniques, and Trends

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China Communications 2023年第7期20卷 1-14页

作者： Yuanzhi He Yuan Li Hao Yin Institute ofSystemsEngineering AMSPLABeijing100141China

In recent years,as giant satellite constellations grow rapidly worldwide,the co-existence between constellations has been widely *** this paper,we overview the co-frequency interference(CFI)among the giant non-geostationary orbit(NGSO)***,we first summarize the CFI scenario and evaluation index among different NGSO *** on statistics about NGSO constellation plans,we analyse the challenges in mitigation and analysis of ***,the CFI calculation methods and research progress are systematically sorted out from the aspects of interference risk analysis framework,numerical calculation and link ***,the feasibility of interference mitigation technologies based on space,frequency domain isolation,power control,and interference alignment mitigation in the NGSO mega-constellation CFI scenario are further sorted ***,we present promising directions for future research in CFI analysis and CFI avoidance.

关键词： co-frequency existence analysis method overview interference avoidance

interference-FREE TOOL POSTURE GENERATION FOR 5-AXIS NC MILLING FREE-FORM SURFACES WITH CYLINDRICAL MILL

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Chinese Journal of Mechanical Engineering 2004年第3期17卷 381-384页

作者： ChenLiping ChenYan HuDejin SchoolofMechanicalandPowerEngineering ShanghaiJiaotongUniversityShanghai200030China SchoolofEnergyandPowerEngineering Xi＇anJiaotongUniversityXi＇an710049China SchoolofMechanicalandPowerEngineering ShanghaiJiaotongUniversityShanghai200030China

The 5-axis NC machining offers the potential of efficient and accuratemachining. However, the present CAM system for 5-axis control is still an unsolved problem due tointerference between tool and surrounding objects. A new method is presented. There are two steps inthis procedure. First, it detects the interference by calculating the shortest distance between thetool-axis and the surrounding surfaces. Then upon the maximum gouging, the interference-free toolposture for 5-axis NC cylindrical milling free-form surfaces is obtained by adjusting tool. Thevalidity of the proposed method has been confirmed by machining an impeller.

关键词： NC machining interference avoidance Computer aided manufacturing

A Pilot Contamination avoidance Based on Pilot Pattern Design for Ultra-Dense Network

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China Communications 2020年第12期17卷 235-246页

作者： Jie Huang Fan Yang Yiwen Gao Zhiming Wang Jun Zhong School of Electrical and Electronic Engineering Chongqing University of TechnologyChongqing 400054China China Mobile Group Chongqing Co.Ltd Chongqing 400044China Electric Power Research Institute China Southern Power GridGuangzhou 510663China State Grid Chongqing Electric Power Company Chongqing 400015China

With the ever-growing number of base stations(BSs)and user equipments(UEs)in ultra-dense networks(UDN),reusing the same pilot sequences among the cells is *** pilot reuse scheme,the channel estimation obtained at a BS contains not only the desired channel-state information(CSI)but also interference from neighboring cells,which can severely degrade CSI estimation performance and adversely affect communication *** this paper we consider a pilot contamination avoidance based on pilot pattern design for UDN where the pilot reuse employed and the interfering users from neighboring cells may be not at lower power levels at the BS compared to the in-cell *** present a novel statistical interference model of sub-carriers to describe the non-deterministic interference from neighboring ***,we provide a pilot pattern design model with non-uniform pilot *** on this,a pilot contamination avoidance based on pilot pattern design is proposed where pilot reuse scheme and the non-deterministic interference from neighboring cells are taken into *** existing interference mitigation approaches,the proposed method eliminates interference through the method of interference avoidance and can be applied to different kinds of channel estimation *** results showed that the proposed approach can effectively avoid the interference and ensure the accuracy of channel estimation.

关键词： ultra-dense networks(UDN) pilot reuse interference avoidance pilot pattern design

Frequency hopping in IEEE 802.15.4 to mitigate IEEE 802.11 interference and fading

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Journal of Systems Engineering and Electronics 2018年第3期29卷 445-455页

作者： JAVED Umer HE Di LIU Peilin YANG Yueming Shanghai Key Laboratory of Navigation and Location-based Services Shanghai Jiao Tong University Shanghai Panchip Microelectronics Co. Ltd

In this paper, we investigate the issues of initialization and deployment of wireless sensor networks（WSNs） under IEEE 802.11 b/g interference and fading channels using frequency hopping（FH）. We propose an FH algorithm for WSNs, which is implemented and tested with a pair of nodes employing IPv6 over low power wireless personal area networks（6 LoWPAN） *** merits and demerits of the proposed FH scheme in WSNs are studied under strong IEEE 802.11 b/g interference and frequency selective fading channels. We compare the performance results of the proposed FH scheme with those obtained by single-channel radio in WSNs, and show that FH maintains very reliable data rates in the presence of adverse conditions where the single-channel radio fails. We determine a minimum center frequency offset of channels between IEEE 802.15.4 and IEEE 802.11 b/g-based networks, which guarantees the error free network operation of IEEE802.15.4 using a single channel. We design a second FH procedure comprising only four free channels（15, 20, 25, and 26） of IEEE 802.15.4 standard, and show that in the presence of nearby IEEE 802.11 b/g interference, the IEEE 802.15.4 data rate using this method is always 98% and more.

关键词： IEEE 802.15.4 wireless sensor networks(WSNs) frequency hopping(FH) interference avoidance coexistence

Radio resource management scheme and outage analysis for network- assisted multi-hop D2D communications

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Digital Communications and Networks 2016年第4期2卷 225-232页

作者： Leila Melki Sameh Najeh Hichem Besbes University of Carthage Higher School of Communications of Tunis COSIM Research Lab Tunisia

In a cellular network it＇s very difficult to make spectrum resource more efficiently. Device-to-Device （D2D） technology enables new service opportunities, and provides high throughput and reliable communication while reducing the base station load. For better total performance, short-range D2D links and cellular links share the same radio resource and the management of interference becomes a crucial task. Here we argue that single-hop D2D technology can be used to further improve cellular networks performance if the key D2D radio resource management algorithms are suitably extended to support multi-hop D2D communications. Aiming to establish a new paradigm for the analysis and design of multi-hop D2D communications, We propose a radio resource allocation for multi-hop D2D routes based on interference avoidance approach in LTE-A networks. On top of that, we investigate the outage probability of D2D communication. We first introduce a new definition of outage probability by considering the maximum distance to be allowable for single-hop transmission. Then we study and analyze the outage performance of a multi-hop D2D route. We derive the general dosed form expression of outage probability of the multi-hop D2D routes. The results demonstrate that the D2D radio, sharing the same resources as the cellular network, provide higher capacity compared to pure cellular communication where all the data is transmitted through the base station. They also demonstrate that the new method of calculation of D2D multi hop outage probability has better performance than classical method defined in the literature.

关键词： D2D Multi-hop interference avoidance Outage probability LTE-A

Distributed Power Control for Energy Conservation in Hybrid Cellular Network with Device-to-Device Communication

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China Communications 2014年第3期11卷 27-39页

作者： TANG Rui ZHAO Jihong QU Hua School of Electronics and Information Engineering Xi'an Jiaotong University Xi'an 710049 Shaanxi Province P. R. China School of Communication and Information Engineering Xi'an University of Posts and Telecommunications Xi'an 710061 ShaanxiProvince P. R. China

Device-to-Device(D2D) communication has been proposed as a promising implementation of green communication to benefit the existed cellular *** order to limit cross-tier interference while explore the gain of short-range communication,we devise a series of distributed power control(DPC) schemes for energy conservation(EC)and enhancement of radio resource utilization in the hybrid ***,a constrained opportunistic power control model is built up to take advantage of the interference avoidance methodology in the presence of service requirement and power ***,biasing scheme and admission control are added to evade ineffective power consumption and maintain the feasibility of the *** feasibility,a non-cooperative game is further formulated to exploit the profit in EC with minor influence on spectral efficiency(SE).The convergence of the DPC schemes is validated and their performance is confirmed via simulation results.

关键词： Device-to-Device communication distributed power control energy conservation interference avoidance biasing scheme admission control non-cooperative game

Adaptive beaconing for collision avoidance and tracking accuracy in vehicular networks

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Journal of Communications and Information Networks 2017年第2期2卷 30-45页

作者： Long Sun Aiping Huang Hangguan Shan Lin Cai College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Information Processing and Communication Networks Hangzhou 310027China University of Victoria Victoria BC V8W 3P6Canada

In vehicular networks,the exchange of beacons among neighboring vehicles is a promising solution to guarantee a vehicle's ***,frequent beaconing under high vehicle density conditions will cause beacon collisions,which are harmful to a vehicle's driving safety and the location tracking *** propose an ABIwRC(Adaptive Beaconing Interval with Resource Coordination)method for a highway *** vehicle broadcasts beacon interval requests,including the intervals needed for both the vehicle's driving safety and location tracking *** RSU(Road Side Unit)allocates resources for a vehicle's beaconing according to the requests from all vehicles and the interference relationship between the vehicles in adjacent *** formulate a resource allocation problem for maximizing the sum utility,which measures the satisfaction of vehicles'*** then transform the optimization problem into a maximum weighted independent set problem,and propose an algorithm to solve this *** results show that the proposed method outperforms the benchmark in terms of beacon reception ratio,vehicle driving safety,and location tracking accuracy.

关键词： vehicular networks beacon driving safety location tracking accuracy maximum weight inde-pendent set interference avoidance