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Joint hybrid beamforming and power splitting design in millimeter-wave simultaneous wireless information and power transfer system

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The Journal of China Universities of Posts and Telecommunications 2019年第2期26卷 59-66页

作者： Bao Tiantian Wen Xiangming Lu Zhaoming Chen Yawen Zheng Wei School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Laboratory of Advanced Information Networks Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and TelecommunicationsBeijing 100876China

A joint hybrid beamforming and power splitting(JHBPS) design problem for simultaneous wireless information and power transfer(SWIPT) in millimeter-wave(mmWave) system is *** considered scenario is a multi-antenna base station(BS) transfers information and energy simultaneously to multiple single-antenna *** adopts hybrid digital and analog beamforming architecture to reduce hardware *** separate acquired signals with power splitters either for information decoding(ID) or energy harvesting(EH).The aim is minimizing total transmission power by joint design of hybrid beamforming and PS under ID and EH *** is difficult to obtain the optimal hybrid beamformer directly since the analog beamformer and digital beamformer are ***,a two-stage algorithm is proposed to solve the *** the first stage,the optimal beamformer and PS ratios are obtained by solving the joint transmission beamforming and PS design *** the second stage,the optimal beamformer is approximated with the product of analog beamformer and digital *** superiority of proposed algorithm over the existing algorithms is demonstrated through ***,the effectiveness of approximation algorithm is testified.

关键词： SWIPT mmWave hybrid analog and digital beamforming

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Deep Deterministic Policy Gradient Based Computation Offloading in Wireless-Powered MEC networks

Deep Deterministic Policy Gradient Based Computation Offload...

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IEEE Globecom Workshops

作者： Ruoqi Liu Xuanlin Liu Sihua Wang Changchuan Yin Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing P. R. China

ISBN: (数字)9781728173078

ISBN: (纸本)9781728173085

With the upsurge of Internet of Things (IoT), mobile edge computing (MEC) and wireless power transfer (WPT) are becoming promising methods to relieve IoT devices from the limited computation capacity and battery capacity. In this paper, we study the joint optimization of the local computing central processing unit (CPU) frequency and the offloading ratio in a dynamic WPTMEC network. In the proposed network, all the IoT devices follow a harvest-then-compute protocol so as to be charged by the MEC server and then compute the tasks. Our goal is to minimize the long-term averaged maximal computing delay with stochastic task arrivals and time-varying wireless channels. It is challenging to find the optimal solution due to the uncertain network information and the non-convex objective function. To tackle this problem, we propose a deep reinforcement learning-based deep deterministic policy gradient (DDPG) framework, which can learn a centralized policy to coordinate the local computing CPU frequencies and offloading ratios of IoT devices. Simulation results show that the proposed DDPG algorithm can achieve up to 73.2% and 16.8% gain in terms of the averaged maximal computing delay compared to the local-computing-only method and the deep Q-network algorithm, respectively.

关键词： Wireless communication Simulation Stochastic processes Delays Central Processing Unit Internet of Things Task analysis

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Joint Beamforming and Artificial Noise Design in Intelligent Reflecting Surface Aided Secure Wireless Communications

Joint Beamforming and Artificial Noise Design in Intelligent...

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International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Pei Liu Kai Zhang Changchuan Yin Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing P. R. China

ISBN: (数字)9781728172361

ISBN: (纸本)9781728172378

In this paper, we study an intelligent reflecting surface (IRS)-assisted secure wireless communication system, in which a multi-antenna access point (AP) communicates with a single antenna legitimate user in the presence of multiple single-antenna eavesdroppers. In order to effectively prevent eavesdroppers from receiving target information so as to improve the security of the network, artificial noise (AN) is injected into the transmit signal of the AP. For the purpose of power efficiency, we study the problem of minimizing the total power consumption subjected to a target secrecy rate constraint in an IRS-assisted secure communication system. In order to solve this non-convex problem, we decompose the problem into a two-level problem and an iterative problem, which are summarized in our solution by optimizing the two sub-problems successively. Numerical results show that our algorithm can effectively reduce the power consumption and improve the system security performance by optimizing the AP transmitting vectors, AN covariance matrix and IRS reflecting phase.

关键词： Wireless communication Signal processing Conferences

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An LSTM Acceleration Engine for FPGAs Based on Caffe Framework 5

An LSTM Acceleration Engine for FPGAs Based on Caffe Framewo...

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5th IEEE International Conference on Computer and Communications, ICCC 2019

作者： He, Junhua He, Dazhong Yang, Yang Liu, Jun Yang, Jie Wang, Siye Beijing University of Posts and Telecommunications Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing100876 China

ISBN: (纸本)9781728147437

Recently, Long Short Term Memory (LSTM) networks have been widely used in sequence-related problem. LSTMs outperform conventional feed-forward neural networks and RNNs in many ways, since they remember patterns selectively for long durations of time. However, due to the recurrent property of LSTMs, it is hard to implement a high computing parallelism on general processors such as CPUs and GPUs. Besides, the huge energy consumption of GPU and CPU computing is a non-negligible issue for data centers. In order to solve the problems above, FPGA emerges as an ideal solution. It has the characteristics of low power and latency, which has natural advantages for the implementation of recurrent neural networks, such as LSTMs. In this paper, we propose to implement an acceleration engine for LSTM network based on FPGAs. By employing fixed-point arithmetic, systolic arrays for matrix multiplication and look up table for activate function, we optimize the LSTM on FPGA in depth. Additionally, we integrate the acceleration engine into Caffe, one of the most popular deep learning framework, to make it easier to deploy. According to the experimental results, our acceleration engine achieves 8.8X and 2.2X gains for performance, 16.9X and 9.6X gains for energy efficiency compared with CPU and GPU, respectively. © 2019 IEEE.

关键词： Field programmable gate arrays (FPGA)

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Low-delay Secure Handover for Space-air-ground Integrated networks

Low-delay Secure Handover for Space-air-ground Integrated Ne...

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IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)

作者： Xinhang Ding Zhilong Zhang Danpu Liu Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing P. R. China

ISBN: (数字)9781728144900

ISBN: (纸本)9781728144917

Recently, space-air-ground integrated network (SAGIN) has been widely concerned which satisfies the emerging requirement of ubiquitous high-rate wireless communication services. Due to the high mobility of satellites and aircraft in SAGIN, user handover occurs frequently. Fast and secure handover is essential to ensure the global seamless coverage of SAGIN. Existing studies mainly focus on improving the authentication security during handover process and reducing the signaling and computation overhead. However, no one optimizes the handover delay with a given security requirement in SAGIN. In this paper, we propose a new handover scheme based on pre-authentication and security context transfer, and optimize the selection of satellite nodes to ensure fast and secure handoffs. Simulation results show that our scheme algorithm reduces the handover delay by 16.92% compared with baseline algorithm.

关键词： Handover Satellite broadcasting Delays Authentication Satellites

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Virtual network Embedding Based on Hybrid Adaptive Genetic Algorithm 5

Virtual Network Embedding Based on Hybrid Adaptive Genetic A...

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5th IEEE International Conference on Computer and Communications, ICCC 2019

作者： Boyang, Liu Muqing, Wu Haosen, Zou Beijing University of Posts and Telecommunications Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing100876 China

ISBN: (纸本)9781728147437

Virtual network embedding (VNE) is one of the central parts of network virtualization, and its main objective is to maximize the revenue of substrate networks(SN). In the previous studies, heuristic algorithms are widely used to solve the embedding problems, but they are liable to trap in local optimum. In addition, they also have slow convergence rates which are caused by ignoring the intrinsic characteristics of the VNE. In this paper, on the first hand, we improve the cross operator of traditional genetic algorithm (GA) to an adaptive cross operator, in order to increase the convergence speed;on the other hand, a simulated annealing algorithm is used to replace the mutation operation, and the simulated annealing idea is adopted to modify the selection operation to avoid the local optimization. The simulation results show that the proposed algorithm has a significant improvement in the VNE acceptance rate and the revenue-to-cost ratio. © 2019 IEEE.

关键词： Simulated annealing

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Cross-domain Interconnection with Time Synchronization in Software-defined Time-Sensitive networks

Cross-domain Interconnection with Time Synchronization in So...

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Asia Communications and Photonics Conference and Exhibition (ACP)

作者： Mengjie Guo Guochu Shou Junli Xue Yihong Hu Yaqiong Liu Zhigang Guo Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China

We propose a software-defined Time-Sensitive networking cross-domain interconnection scheme based on a coordinate controller and conduct a time synchronization experiment. The results show the scheme is valid in time ... 详细信息

ISBN: (数字)9781943580828

ISBN: (纸本)9781728176567

关键词： Asia Optical fiber communication Synchronization Photonics

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The Service Metrics and Performance Analysis of Internet Time Service

The Service Metrics and Performance Analysis of Internet Tim...

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IEEE Symposium on network Operations and Management

作者： Jing Ling Guochu Shou Mengjie Guo Yihong Hu Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communications Engineering Beijing University of Posts and Telecommunications Beijing China

ISBN: (数字)9781728149738

ISBN: (纸本)9781728149745

An increasing number of Industry Internet of Things (IIoT) applications put forward the requirements for strict time synchronization and accurate time service from providers. In order to indicate the time service performance of the Internet Time Service Providers (TSPs) on user sides, we build an Internet time service monitoring system which can obtain the real-time data of time service through the Internet. The monitoring system records the time service's performance from three major categories: NTP pool projects, National Metrology Institutes and Commercial Organizations. After that, we propose three service metrics, in terms of Availability, Stability and Accuracy, to evaluate the performance of time service provided by TSPs. On the other hand, a novel anomaly detection algorithm is proposed to gather the statistics of abnormal data and then remove the abnormal data. Experimental results show that 56 TSPs' availability are more than 95%. It indicates that a longer transmission path results in a lower availability. The further analyzed results also denote that the link hops have no correlations of Availability, Stability and Accuracy. Moreover, the relationship between Stability and Accuracy is positively correlated.

关键词：

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Privacy-Protecting Reputation Management Scheme in IoV-based Mobile Crowdsensing

Privacy-Protecting Reputation Management Scheme in IoV-based...

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International Conference on Mobile Ad-hoc and Sensor networks, MSN

作者： Zhifei Wang Luning Liu Luhan Wang Xiangming Wen Wenpeng Jing Beijing Key Lab of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing Laboratory of Advanced Information Networks Beijing China

ISBN: (数字)9781728199160

ISBN: (纸本)9781728192369

Mobile crowdsensing (MCS) has appeared as a viable solution for data gathering in Internet of Vehicle (IoV). As it utilizes plenty of mobile users to perform sensing tasks, the cost on sensor deployment can be reduced and the data quality can be improved. However, there exist two main challenges for the IoV-based MCS, which are the privacy issues and the existence of malicious vehicles. In order to solve these two challenges simultaneously, we propose a privacy-protecting reputation management scheme in IoV-based MCS. In particular, our privacy-protecting scheme can execute quickly since its complexity is extremely low. The reputation management scheme considers vehicle's past behaviors and quality of information. In addition, we introduced time fading into the scheme, so that our scheme can detect the malicious vehicles accurately and quickly. Moreover, latency in the IoV must be exceedingly low. With the help of the mobile edge computing (MEC) which is deployed on the base station side and has powerful computing capability, the latency can be greatly reduced to meet the requirements of the IoV. Simulation results demonstrate effectiveness of our reputation management scheme in resisting malicious vehicles, which can assess the reputation value accurately and detect the malicious vehicles quickly while protecting the privacy.

关键词： Fading channels Privacy Crowdsensing Simulation Sensors Complexity theory Task analysis

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Design of Circular Polarization Antenna Array Based on Sequential Phase Feed network

Design of Circular Polarization Antenna Array Based on Seque...

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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： Hui Yang Weijun Hong Jiaqi Cai Yaping Jin Beijing Laboratory of Advanced Information Network Beijing University of Posts and Telecommunications Beijing China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

A novel circular polarized microstrip 4-unit array antenna based on sequential phase (SP) feed network is proposed in this paper. The proposed antenna is designed to work at 33 GHz. Four square tangential circular polarization patches are connected to the SP feeding network to form a 2×2 microstrip array to achieve better circular polarization performance. A metasurface superstrate is designed above the antenna to improve the antenna gain. Simulation results show that the return loss bandwidth of the proposed antenna for| S11|

关键词： Phased arrays Polarization Microstrip antenna arrays Bandwidth Antenna feeds Metasurfaces Broadband antennas

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