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ergodic capacity Evaluation of Multi-Hop Decode-and-Forward MIMO-OFDM Relaying Network

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Computers, Materials & Continua 2021年第9期68卷 3133-3145页

作者： Latif Jan Mohammad Haseeb Zafar Abdul Waheed Mahdi Zareei Faisal Alanazi Department of Electrical Engineering University of Engineering&TechnologyPeshawar25120Pakistan Department of Information Technology Hazara UniversityMansehra21120Pakistan Tecnologico de Monterrey School of Engineering and SciencesZapopan45201Mexico Department of Electrical Engineering Prince Sattam Bin Abdulaziz UniversityCollege of EngineeringAl Kharj16278Saudi Arabia

Spatial diversity plays a significant role in wireless communication systems,including the Fourth Generation(4G)and Fifth Generation(5G)systems,and it is expected to be a fundamental part of the future wireless communication systems as *** Multiple-Input Multiple-Output(MIMO)technology,which is included in the IEEE 802.16j standard,still holds the most crucial position in the 4G spectrum as it promises to improve the throughput,capacity,spectral,and energy efficiency of wireless communication systems in the *** makes MIMO a viable technology for delay constrained medical and health care *** paper presents an approximate closed-form expression of the ergodic capacity for the Decode-and-Forward(DF)protocol MIMO-Orthogonal Frequency Division Multiplexing(OFDM)relaying *** MIMO-OFDM is highly valuable for modern high-speed wireless communication systems,especially in the medical sciences,its performance degrades in multi-hop relay ***,in this paper,an approximate closed-form expression is derived for an end-to-end ergodic capacity of multi-hop DF MIMO-OFDM wireless communication system has been ***-Carlo simulations are conducted to verify the performance of the presented analysis regarding the capacity(bits/s/Hz)for different SNR-dB values for single,2×2,4×4,and multi-hop DF MIMOOFDM *** presented results provide useful insights for the research on the end-to-end ergodic capacity evaluation.

关键词： Multiple-input multiple-output system decode-and-forward protocol orthogonal frequency division multiplexing ergodic capacity

ergodic capacity ANALYSIS FOR SIMO COGNITIVE FADING CHANNEL IN SPECTRUM SHARING ENVIRONMENT

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Journal of Electronics(China) 2010年第5期27卷 677-685页

作者： Yang Yang Wang Jinlong Wu Qihui Liu Xin Institute of Communication Engineering PLA University of Science and Technology Nanjing 210007China

In this paper,we consider the spectrum sharing Cognitive Radio(CR) system,wherein Single-Input Multi-Output(SIMO) cognitive fading channel is *** to the average in-terference constraint of primary user,the ergodic capacity of cognitive user involving joint beamforming and power control is *** derive the optimal joint beamforming and power control strategy and deduce the general integral expression for ergodic ***,under different channel fadings including Raleigh fading,Nakagami-m fading and Lognormal shadowing fading,the specific expressions of ergodic capacity for SIMO cognitive channel are *** of the expressions are presented in closed-form or with some special integral *** amount of simulations are conducted to corroborate our theoretical results.

关键词： Cognitive Radio (CR) Beamforming Power control ergodic capacity Single-Input Multi-Output (SIMO)

ergodic capacity FORMULA OF MIMO-OFDM SYSTEMS UNDER CORRELATED FREQUENCY SELECTIVE RAYLEIGH FADING CHANNELS

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Journal of Electronics(China) 2007年第5期24卷 588-592页

作者： Pang Jiyong Li Jiandong Zhao Linjing Broadband Wireless Communications Lab Information Science InstituteState Key Lab of Integrated Service Networks Xidian University Xi＇an 710071 China

An explicit formula for the ergodic capacity of Orthogonal Frequency Division Multiplexing (OFDM)-based Multiple-Input Multiple-Output (MIMO) systems under correlated frequency selective Rayleigh channels is derived,by simplifying the channel response matrix in frequency domain into the so-called Kronecker model composed of three kinds of correlations,*** tap gain correlation and spatial fading correlations at both transmitter and *** derived formula is very simple and convenient for one to estimate the effects of all three kinds of correlations on MIMO-OFDM *** taps are independent,there is a very simple expression for the ergodic *** case of tap correlation,the capacity formula could be further given in an integral *** validity of the new formula is verified and the effects of correlations,delay spread as well as the number of subcarriers on the ergodic capacity are evaluated via Monte Carlo simulations.

关键词： Multiple-Input Multiple-Output (MIMO) Orthogonal Frequency Division Multiplexing(OFDM) Kronecker product Channel correlation ergodic capacity

ergodic capacity analysis for device-to-device communication underlaying cellular networks

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Journal of Southeast University(English Edition) 2015年第3期31卷 333-338页

作者：李旭杰张洪浪张文娜李文峰河海大学计算机与信息学院南京210098 复旦大学上海市智能信息处理重点实验室上海200433 中南民族大学智能无线通信湖北省重点实验室武汉430074 南京大学电子科学与工程学院南京210023

The ergodic capacity of device-to-device （D2D） communication underlaying cellular networks is analyzed. First,the D2D communication model is introduced and the interference during uplink period and downlink period is *** a D2D communication system,since it is very difficult to obtain the instantaneous channel state information （CSI）,assume that only the transmitters know the statistical CSI and the channel coefficient follows an independent complex Gaussian *** on the assumptions,for the uplink period,the signal to interference plus noise ratio （SINR）of the D2D user equipments（DUEs）is expressed. Then the cumulative distribution function （CDF ） and probability distribution function （PDF）formulae of the SINR of the DUEs are *** on the SINR formulae during the uplink period,the ergodic capacity formula of the uplink period is derived. Subsequently, using the same methods,the ergodic capacity formula of the downlink period is *** simulation results show that the DUEs can still obtain a high ergodic capacity even in the case of a large number of *** result can be applied to the design and optimization of D2D communications.

关键词： D2D ergodic capacity cellular networks

Statistical CSI based design for intelligent reflecting surface assisted MISO systems

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Science China(Information Sciences) 2020年第12期63卷 211-220页

作者： Xiaoling HU Junwei WANG Caijun ZHONG College of Information Science and Electronic Engineering Zhejiang University

This paper considers an intelligent reflecting surface(IRS) aided multiple-input single-output communication system, where statistical channel state information(CSI) is exploited for transmit beamforming and IRS beamforming. A tight upper bound is derived for the ergodic capacity of the system. Based on which, the joint optimization of transmit beam and IRS beam are studied. Depending on whether a line-of-sight path exists between the access point and user, two different cases, namely, Rician fading and Rayleigh fading, are separately treated. Specifically, for the Rician fading case, an iterative algorithm is proposed, which is guaranteed to converge. For the Rayleigh fading case, closed-form designs are obtained for the transmit beam and IRS beam. Simulation results show the proposed beamforming scheme achieves similar performance as the benchmark algorithm requiring instantaneous CSI.

关键词： beamforming IRS MISO statistical CSI ergodic capacity

capacity Analysis and Optimization of Cognitive Ultra Wideband Networks

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China Communications 2010年第2期7卷 109-116页

作者： Zhao Chenglin Xu Fangmin Sun Xuebin Sun Songlin Jiang Ting Key Laboratory of Universal Wireless Communication Ministry of Education Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 P. R. China Samsung China Communication R＆D Center Beijing 100125 P. R. China

The integration of cognitive radio and Ultra wideband (UWB) networks has attracted lots of research interests. Cognitive UWB networks not only provide very high data rates but also guarantee the uninterrupted communication of primary system operated in the same frequency band. In this work, the problem of the capacity analyses of cognitive UWB networks is investigated. Different from the conventional cognitive spectrum sharing model which can only utilize the idle spectrum hole, the cognitive UWB system can operate adaptively based on spectrum sensing results. Taking into account several factors such as the transmission power constraint of UWB, the interference constraint of the receivers in primary systems, the secondary UWB network capacity problem is modeled as a convex optimization problem over the transmission power. The optimal power allocation strategy and algorithm are derived based on this optimization problem. Two cases (Perfect Spectrum Sensing and Imperfect Spectrum Sensing) are studied in the paper. Numerical simulation results show that the proposed adaptive power allocationscheme improves the ergodic and outage capacity under both transmission power and interference constraints compared with constant transmission power scheme.

关键词： cognitive radio UWB ergodic capacity transmission power allocation

Antenna Selection in Energy Harvesting Relaying Networks Using Q-Learning Algorithm

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China Communications 2021年第4期18卷 64-75页

作者： Daliang Ouyang Rui Zhao Yuanjian Li Rongxin Guo Yi Wang College of Information Science and Engineering Huaqiao UniversityXiamen 361021China Centre for Telecommunications Research King’s College LondonLondon WC2R 2LSU.K. School of Electronics and Communication Engineering Zhengzhou University of AeronauticsZhengzhou 450046China China National Digital Switching System Engineering and Technological Research Center Zhengzhou 450002China

In this paper,a novel opportunistic scheduling(OS)scheme with antenna selection(AS)for the energy harvesting(EH)cooperative communication system where the relay can harvest energy from the source transmission is *** this considered scheme,we take into both traditional mathematical analysis and reinforcement learning(RL)scenarios with the power splitting(PS)factor *** the case of traditional mathematical analysis of a fixed-PS factor,we derive an exact closed-form expressions for the ergodic capacity and outage probability in general signal-to-noise ratio(SNR)***,we combine the optimal PS factor with performance metrics to achieve the optimal transmission ***,based on the optimized PS factor,a RL technique called as Q-learning(QL)algorithm is proposed to derive the optimal antenna selection *** highlight the performance advantage of the proposed QL with training the received SNR at the destination,we also examine the scenario of QL scheme with training channel between the relay and the *** results illustrate that,the optimized scheme is always superior to the fixed-PS factor *** addition,a better system parameter setting with QL significantly outperforms the traditional mathematical analysis scheme.

关键词： Q-learning optimal PS factor outage probability ergodic capacity antenna selection

Analysis of subchannel reusable probability and capacity for frequency-reused femtocell networks under frequency partitioning strategy

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 1-10页

作者： LI Hong-jia HU Dan XU Xiao-dong CI Song TANG Hui High Performance Network Laboratory Institute of Acoustics Chinese Academy of Sciences Beijing 100876 China Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Femtocell is a promising technology to improve network performance with low-power and cost-beneficial small base stations. However, the interference-limited reality in femtocell networks makes interference and resource management the key to achieving the benefits of femtocell networks. In this paper, the following contributions are made step by step： first, on the basis of the interference temperature model （ITM） in cognitive radio （CR） technique and the network architecture of the third generation partnership project （3GPP） long term evolution advanced （LTE-A）, the problem model of optimizing the capacity of the femtocell-reused subchannel is established under the frequency partitioning strategy, jointly considering the average interference constraint and the instantaneous interference constraint. Second, utilizing the convex theory, optimal power allocation of the femtocell-reused subchannel is derived. Third, under Rayleigh fading channel, closed-form expressions of the subchannel reusable probability and capacity are derived. At last, numerical results are conducted to confirming our analytical results, which could provide theoretical guidance for frequency resource allocation of femtocell network deployments.

关键词： femtocell frequency reuse power allocation reusable probability ergodic capacity Rayleigh channel

Dual Waterfilling Power Allocation Algorithm in MIMO Systems

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China Communications 2009年第3期6卷 144-149页

作者： Rong Mei Zhu Shihua Li Feng School of Electronics and Information Engineering Xi＇an Jiaotong University Xi＇an 710049 China

Aiming at the problem of resource allocation in multiuser multi-input multi-output (MIMO)systems,a new power allocation algorithm based on dual waterfilling is *** diagonalization is adopted to cancel the inter-user interference,and then the complete diagonalization method is employed to derive the spatial sub-channels for each *** overall power of the system is divided among users based on each user’s large scale fading;then the power of each user is further allocated to its spatial sub-channels based on the small scale *** results show that compared with the existing resource allocation strategies,the proposed algorithm can provide more ergodic capacity for multi-user MIMO *** the total transmit power is 100w,it has 15%capacity advantage over the traditional waterfilling method.

关键词： waterfilling resource allocation ergodic capacity