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Beam Training and Tracking in mmWave Communication:A Survey

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China Communications 2024年第6期21卷 1-22页

作者： Wang Yi Wei Zhiqing feng zhiyong Yangtze Delta Region Institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324003China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

Communicating on millimeter wave(mmWave)bands is ushering in a new epoch of mobile communication which provides the availability of 10 Gbps high data rate ***,mmWave links are easily prone to short transmission range communication because of the serious free space path loss and the blockage by *** overcome these challenges,highly directional beams are exploited to achieve robust links by hybrid *** aligning the transmitter and receiver beams,*** training,is vitally important to high data rate ***,it may cause huge overhead which has negative effects on initial access,handover,and ***,the mobility patterns of users are complicated and dynamic,which may cause tracking error and large tracking *** efficient beam tracking method has a positive effect on sustaining robust *** article provides an overview of the beam training and tracking technologies on mmWave bands and reveals the insights for future research in the 6th Generation(6G)mobile ***,some open research problems are proposed to realize fast,accurate,and robust beam training and *** hope that this survey provides guidelines for the researchers in the area of mmWave communications.

关键词： 6G beam tracking beam training beamforming mmWave

A Survey of Security Issues in Cognitive Radio Networks

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China Communications 2015年第3期12卷 132-150页

作者： LI Jianwu feng Zebing feng zhiyong ZHANG Ping Network Information Processing Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and Telecommunications Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

In the last decade,cognitive radio(CR) has emerged as a major next generation wireless networking technology,which is the most promising candidate solution to solve the spectrum scarcity and improve the spectrum ***,there exist enormous challenges for the open and random access environment of CRNs,where the unlicensed secondary users(SUs) can use the channels that are not currently used by the licensed primary users(PUs) via spectrum-sensing *** of this access method,some malicious users may access the cognitive network arbitrarily and launch some special attacks,such as primary user emulation attack,falsifying data or denial of service attack,which will cause serious damage to the cognitive radio *** addition to the specifi c security threats of cognitive network,CRNs also face up to the conventional security threats,such as eavesdropping,tampering,imitation,forgery,and noncooperation etc..Hence,Cognitive radio networks have much more risks than traditional wireless networks with its special network *** this paper,we considered the security threats from passive and active ***,the PHY layer security is presented in the view of passive attacks,and it is a compelling idea of using the physical properties of the radio channel to help provide secure wireless ***,malicious user detection is introduced in the view of active attacks by means of the signal detection techniques to decrease the interference and the probabilities of false alarm and missed ***,we discuss the general countermeasures of security threats in three *** particular,we discuss the far reaching effect of defensive strategy against attacks in CRNs.

关键词： CRNs security physical layer security security capacity active attacks passive attacks

Spectrum Allocation and Performance Analysis for Backhauling of UAV Assisted Cellular Network

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China Communications 2019年第8期16卷 72-81页

作者： Lei Ji Jingran Chen zhiyong feng Key Laboratory of Universal Wireless Communications Ministry of Education Wireless Technology Innovation Institute (WTI)Beijing University of Posts and Telecommunications

To reinforce the coverage and QoS(quality of service) of on-ground cellular communication system, unmanned aerial vehicles which are carrying small cells are deployed in some emergency and disaster areas. Although ASCs(aerial small cells) can provide a higher probability of LoS(line-of-sight) transmission, the wireless backhaul link will bring extra interference to the whole system if not well designed. Therefore, in this paper, we study the backhaul scheme for UAV-assist cellular network. We first analyze the interference environments of UAV-assist cellular network considering the IBOG(In-Band to On-Ground), OBOG(Out-of-Band to On-Ground) and IBTU(In-Band to Tethered-UAV) backhauling mode, and give the descriptions of the performance metrics for each mode. Then, the considered problem is formulated as an optimization of achievable rate. We derive the optimal solutions for the involved three backhauling modes for ASCs respectively, and closed-form optimal value for each mode is acquired with proof. We also give a pseudo-code form of our proposed optimal access/backhaul spectrum allocation algorithm. The simulation results indicate that the proposed scheme can deliver a significant gain, while IBTU performs best among proposed backhauling modes.

关键词： UAV backhauling spectrum allocation

Effective capacity of delay quality-of-service constrained spectrum sharing cognitive radio with outdated channel feedback

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Science China(Information Sciences) 2013年第6期56卷 115-127页

作者： XU Ding feng zhiyong ZHANG Ping Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications

In this paper,we consider a spectrum sharing cognitive radio network coexisting with a primary ***,the channel state information(CSI) between the secondary transmitter and the primary receiver is assumed to be outdated due to channel feedback *** secondary user(SU) is assumed to satisfy a given delay quality-of-service(QoS) constraint as well as the average interference power *** aim to derive the maximum arrival rate of the SU under aforementioned constraints with the outdated *** this respect,we derive the optimal power allocation to achieve the maximum effective capacity,and further derive the effective *** closed-form expressions for the lower and upper bounds on the effective capacity are also *** addition,we obtain the effective capacities under two widely adopted adaptive transmission schemes,i.e.,optimal power and rate allocation(OPRA) and truncated channel inversion with fixed rate(TIFR).Numerical results are conducted to corroborate our *** is shown that the effective capacities of the SU under various transmission schemes are insensitive to the channel correlation coefficient especially under low channel correlation *** is also shown that the lower and upper bounds on the effective capacity are significantly tight under stringent delay QoS constraint.

关键词： cognitive radio effective capacity outdated channel feedback delay QoS constraint interferencepower constraint

A Multikey Rank Model Based on Ontology for Large-Scale Semantic Data

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Chinese Journal of Electronics 2014年第1期23卷 119-123页

作者： JIANG Yang feng zhiyong WANG Xin School of Computer Science and Technology Tianjin University

In order to provide users with intelligent retrieval services over large-scale semantic data, this paper proposes a Multikey Rank model. ORDPATHs is adopted to encode ontology classes defined in TBox and an inverted index is constructed according to the structured characteristics and semantic association of RDF data. A new query mode with one primary keyword and several auxiliary keywords is designed. To reflect the user’s perference objectively, the membership degree for ontology classes corresponding to the primary keyword is calculated based on the evidence theory and thus the Multikey Rank algorithm is formulated by extending the BM25 F model accordingly. The proposed model was implemented in the selfdeveloped distributed large-scale RDF data server "Jingwei" and experimental results show that compared with BM25 F, the evaluation indexes for P@5, P@10, P@15 and MAP are improved by 27.6%, 24.3%, 18.5% and 3.7%, respectively.

关键词： Semantic retrieval Ontology Ranking Resource description framework(RDF) Keyword

Multi-Agent Reinforcement Learning for Resource Allocation in Io T Networks with Edge Computing

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China Communications 2020年第9期17卷 220-236页

作者： Xiaolan Liu Jiadong Yu zhiyong feng Yue Gao Department of Electronic Engineering and Computer Science Queen Mary University of LondonLondon E14NSU.K Beijing University of Posts and Telecommunications BeijingChina Peng Cheng Laboratory and also with the University of Surrey GU27XHU.K

To support popular Internet of Things(IoT)applications such as virtual reality and mobile games,edge computing provides a front-end distributed computing archetype of centralized cloud computing with low latency and distributed data ***,it is challenging for multiple users to offload their computation tasks because they are competing for spectrum and computation as well as Radio Access Technologies(RAT)*** this paper,we investigate computation offloading mechanism of multiple selfish users with resource allocation in IoT edge computing networks by formulating it as a stochastic *** user is a learning agent observing its local network environment to learn optimal decisions on either local computing or edge computing with a goal of minimizing long term system cost by choosing its transmit power level,RAT and sub-channel without knowing any information of the other *** users’decisions are coupling at the gateway,we define the reward function of each user by considering the aggregated effect of other ***,a multi-agent reinforcement learning framework is developed to solve the game with the proposed Independent Learners based Multi-Agent Q-learning(IL-based MA-Q)*** demonstrate that the proposed IL-based MA-Q algorithm is feasible to solve the formulated problem and is more energy efficient without extra cost on channel estimation at the centralized ***,compared with the other three benchmark algorithms,it has better system cost performance and achieves distributed computation offloading.

关键词： edge computing multi-agent reinforcement learning internet of things

A Novel Automatic Modulation Classification Method Based on Dictionary Learning

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China Communications 2019年第1期16卷 176-192页

作者： Kezhong Zhang Li Xu zhiyong feng Ping Zhang Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Institute of Computing Technology Chinese Academy of Sciences State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

Automatic Modulation Classification(AMC) is an important technology used to recognize the modulation type.A dictionary set was trained via signals with known modulation schemes in cooperative *** we classify the modulation scheme of the signals received in the non-cooperative environment according to its sparse ***,we proposed a novel approach called Fast Block Coordinate descent Dictionary Learning(FBCDL).Moreover,the convergence of FBCDL was proved and we find that our proposed method achieves lower *** results indicate that our proposed FBCDL achieves better classification accuracy than traditional methods.

关键词： modulation classification non-cooperative scenarios dictionary learning sparse coefficient

Coexistence Analysis between 5G System and Fixed- Satellite Service in 3400-3600 MHz

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China Communications 2018年第11期15卷 25-32页

作者： Haifeng Tan Yanjie Liu zhiyong feng Qixun Zhang Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China The State Radio Monitoring Center Shaanxi Monitoring Station Xi'an 710200 China

The 3400-3600 MHz band is one of the most important candidate frequency bands for the rollout of 5 G system. However, the coexistence between 5 G system and fixed-satellite service(FSS) in this frequency band is one of the most challenging problems for both academic researchers and industry engineers. In this paper, the saturation interference from 5 G base stations to the existing FSS above 3600 MHz is analyzed and the coexistence solution is achieved, which can reduce the interference and guarantee the coexistence between 5 G system and FSS. Furthermore, the Monte Carlo simulation, laboratory test and field test are carried out to verify the coexistence *** show that an isolation distance of 1-2 km is required to avoid the saturation interference in terms of the adjacent bands *** further reduce the isolation distance to 50 m, additional isolation of 35 dB will be necessary, which can be fulfilled by installing a filter at the input port of LNB from a real implementation perspective.

关键词： 5G system fixed-satellite service coexistence analysis

A Cyber–Physical Routing Protocol Exploiting Trajectory Dynamics for Mission-Oriented Flying Ad Hoc Networks

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Engineering 2022年第12期19卷 217-227页

作者： Die Hu Shaoshi Yang Min Gong zhiyong feng Xuejun Zhu School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China China Academy of Launch Vehicle Technology Beijing 100076China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing 100876China

As a special type of mobile ad hoc network(MANET),the flying ad hoc network(FANET)has the potential to enable a variety of emerging applications in both civilian wireless communications(e.g.,5G and 6G)and the defense *** routing protocol plays a pivotal role in ***,when designing the routing protocol for FANET,it is conventionally assumed that the aerial nodes move *** is clearly inappropriate for a mission-oriented FANET(MO-FANET),in which the aerial nodes typically move toward a given destination from given departure point(s),possibly along a roughly deterministic flight path while maintaining a well-established formation,in order to carry out certain *** this paper,a novel cyber–physical routing protocol exploiting the particular mobility pattern of an MO-FANET is proposed based on cross-disciplinary integration,which makes full use of the missiondetermined trajectory dynamics to construct the time sequence of rejoining and separating,as well as the adjacency matrix for each node,as prior *** with the existing representative routing protocols used in FANETs,our protocol achieves a higher packet-delivery ratio(PDR)at the cost of even lower overhead and lower average end-to-end latency,while maintaining a reasonably moderate and stable network jitter,as demonstrated by extensive ns-3-based simulations assuming realistic configurations in an MO-FANET.

关键词： Cyber-physical system Flying ad hoc network Routing protocol Trajectory dynamics Unmanned aerial vehicle