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mutual Information Maximization via Joint Power Allocation in Integrated Sensing and Communications System

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China Communications 2024年第2期21卷 129-142页

作者： Jia Zhu junsheng mu Yuanhao Cui Xiaojun Jing School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ISAC, we propose a design scheme based on spectrum sharing, that is,to maximize the mutual information(MI) of radar sensing while ensuring certain communication rate and transmission power constraints. In the proposed scheme, three cases are considered for the scattering off the target due to the communication signals,as negligible signal, beneficial signal, and interference signal to radar sensing, respectively, thus requiring three power allocation schemes. However,the corresponding power allocation schemes are nonconvex and their closed-form solutions are unavailable as a consequence. Motivated by this, alternating optimization(AO), sequence convex programming(SCP) and Lagrange multiplier are individually combined for three suboptimal solutions corresponding with three power allocation schemes. By combining the three algorithms, we transform the non-convex problem which is difficult to deal with into a convex problem which is easy to solve and obtain the suboptimal solution of the corresponding optimization problem. Numerical results show that, compared with the allocation results of the existing algorithms, the proposed joint design algorithm significantly improves the radar performance.

关键词： coexistence communications multicarrier radar mutual information spectrum sharing

Joint Spectrum Sensing Based on Variance and Correlation Analysis

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China Communications 2017年第10期14卷 219-227页

作者： junsheng mu Xiaojun Jing Hai Huang Ning Gao Laboratory of Biological Recognition and Information Application Beijing University of Posts and Telecommunications Key Laboratory of Trustworthy Distributed Computing and Service Ministry of Education 100876 China

In this paper, a novel detection criterion is proposed to decide whether primary user(PU) exists based on joint analysis of the variance and correlation for observation signal,considering a correlation within the observed signal. Simultaneously, the corresponding detection thresholds are also designed. Simulation experiments verify the proposed method suits for the observation signal in Additive White Gaussian Noise(AWGN), Rayleigh,Rician channel and the detection performance is improved greatly.

关键词： spectrum sensing cognitive radio OFDM rayleigh AWGN

A Blind Spectrum Sensing Based on Low-Rank and Sparse Matrix Decomposition

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China Communications 2018年第8期15卷 118-125页

As a crucial component in Cognitive Radio(CR) networks, spectrum sensing has been attracting lots of attention. Some conventional methods for spectrum sensing are sensitive to uncertain signal and noise, its applicability is limited thereof. In this paper, a novel blind spectrum sensing method is proposed, where low-rank and sparse matrix decomposition is applied to the observation signal of a CR in the frequency domain. Then the ratio of the energy of the sparse part and the received signal in the time domain is considered as the criterion to decide whether the radio frequency band is idle by means of a comparison with a predefined threshold. The proposed method is independent of prior knowledge of signal and white noise, and has a better detection performance. Simulation experiments verify the performance of the proposed method in additive white Gaussian noise(AWGN), Rayleighand Rician channels.

关键词： spectrum sensing cognitive radio OFDM Rayleigh AWGN

Intelligent UAV Based Energy Supply for 6G Wireless Powered IoT Networks

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China Communications 2024年第9期21卷 321-337页

作者： Miao Jiansong Chen Haoqiang Wang Pengjie Li Hairui Zhao Yan mu junsheng Yan Shi School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,we develop a 6G wireless powered Internet of Things(IoT)system assisted by unmanned aerial vehicles(UAVs)to intelligently supply energy and collect data at the same *** our dual-UAV scheme,UAV-E,with a constant power supply,transmits energy to charge the IoT devices on the ground,whereas UAV-B serves the IoT devices by data collection as a base *** this framework,the system's energy efficiency is maximized,which we define as a ratio of the sum rate of IoT devices to the energy consumption of two UAVs during a fixed working *** the constraints of duration,transmit power,energy,and mobility,a difficult non-convex issue is presented by optimizing the trajectory,time duration allocation,and uplink transmit power of *** tackle the non-convex fractional optimization issue,we deconstruct it into three subproblems and we solve each of them iteratively using the descent method in conjunction with sequential convex approximation(SCA)approaches and the Dinkelbach *** simulation findings indicate that the suggested cooperative design has the potential to greatly increase the energy efficiency of the 6G intelligent UAV-assisted wireless powered IoT system when compared to previous benchmark systems.

关键词： 6G wireless powered network energy efficiency IoT intelligent network UAV communication

A Brief Introduction on Joint Radar and Communication Systems

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Journal of Beijing Institute of Technology 2021年第1期30卷 60-68页

作者： Jia Zhu Fangpei Zhang Yuanhao Cui junsheng mu Ronghui Zhang Xiaojun Jing School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Information Science Research Institute of China Electronics Technology Group Corporation Beijing 100846China

Joint radar and communication(JRC)technology is gradually becoming an essential approach to alleviating spectral *** and communications systems were designed with common spectral and hardware resources to reduce size,improve performance,reduce cost,and decongest the *** approaches have been proposed to achieve the coexistence of radar and communication *** paper mainly focuses on the research directions of radar communication coexistence(RCC)and dual-function radar communication systems(DFRC)in JRC *** summarize and analyze the existing research problems in the JRC *** to the characteristics and advantages of JRC technology,we highlight several potentials in military and commercial applications.

关键词： joint radar and communication radar-communication coexistence dual-functional radar communication spectrum sharing

基于无位置传感器电流型风力发电系统的PMSG控制

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太阳能学报 2012年第10期33卷 1676-1682页

作者：茆美琴穆俊升合肥工业大学教育部光伏系统工程研究中心合肥230009

基于背靠背式电流型变流控制的直驱永磁同步风力发系统,针对风力发电系统中测速编码器易受干扰以及成本和维修费用增加的问题,提出一种无位置传感器的永磁同步发电机控制方法。该方法基于对永磁同步发电机的模型分析,采用锁相环(PLL)估... 详细信息

基于背靠背式电流型变流控制的直驱永磁同步风力发系统,针对风力发电系统中测速编码器易受干扰以及成本和维修费用增加的问题,提出一种无位置传感器的永磁同步发电机控制方法。该方法基于对永磁同步发电机的模型分析,采用锁相环(PLL)估算法和模型参考自适应法(MRAS)分别进行转子位置和转速估算,利用估算的转子位置和转速对电流型直驱风力发电系统的永磁同步发电机进行转子磁链定向矢量控制(RFOVC)。仿真实验结果表明,基于PLL的PMSG RFOVC策略比基于MRAS的PMSG RFOVC策略具有更好的稳态及动态性能。

关键词：无速度传感器控制永磁同步发电机电流源型变换器 PLL 转子磁链定向矢量控制

Cardiac surgical operation after renal transplantation

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Chinese Medical Journal 2014年第10期127卷 1990-1991页

作者： mu junsheng Zhou Fan Li Xianshuai Zhang Jianqun Bo Ping Department of Cardiac Surgery Beijing Anzhen Hospital Capital Medical University Beijing Institute of Heart Lung and Blood Vessel Diseases Beijing 100029 China Department of Echocardiagraphy General Hospital of Chinese People's Armed Police Forces Beijing 100039 China

Several studies reported the impact of cardiac surgical operation on morbidity and mortality in renal transplant recipients as well as on renal graft function and safety and effect of immunosuppressant medication.1-3 However,few data are available about the risk and immunosuppressant medication in patients who undergo cardiac surgical operation after successful renal transplantation,especially in patients who underwent offpump coronary artery bypass grafting （CABG） with previous renal *** research provides important insights into the immunosuppressive management of a patient requiring valve replacement or CABG after renal transplantation during the perioperative period.

关键词： cardiac surgical operation renal transplantation immunosuppressive

Aortic valve replacement for quadricuspid aortic valve with regurgitation and stenosis in a renal transplant recipient

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Chinese Medical Journal 2014年第16期127卷 3033-3033页

作者： mu junsheng Department of Cardiac Surgery Beijing Anzhen Hospital Capital Medical University Institute of Heart Lung and Blood Vessel Diseases Beijing 100029China

A66-year-old woman presented to the hospital with a 5-year history of dyspnea on exertion, which had worsened over the past month. She had received a kidney transplant 9 years ago. Physical examination revealed a blood pressure of 105/60 mmHg and heart rate of 89 beats/min. Cardiac auscultation revealed a grade 2/6 systolic murmur over the aortic area and a grade 3/6 diastolic murmur over the left sternal border. Laboratory tests showed urea 7.8 mmol/L,

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基于特征值置换的子空间语音增强算法

计算机工程 2016年第2期42卷 272-277,282页

作者：孙成立穆俊生南昌航空大学图像处理与模式识别重点实验室南昌330063 南昌航空大学信息工程学院南昌330063

为提高重构语音质量,提出一种子空间语音增强算法。在内嵌式预白化子空间方法的基础上,用特征值置换增强语音效果。将纯净语音和噪声的协方差矩阵进行广义特征值分解后,大特征值分量包含纯净语音信息,而小特征值分量包含噪声信息,待特... 详细信息

为提高重构语音质量,提出一种子空间语音增强算法。在内嵌式预白化子空间方法的基础上,用特征值置换增强语音效果。将纯净语音和噪声的协方差矩阵进行广义特征值分解后,大特征值分量包含纯净语音信息,而小特征值分量包含噪声信息,待特征值排序后,用相邻的大特征值分量置换小特征值分量,可有效提高语音帧的相关性,获得更好的增强语音信号。相比传统的子空间方法,该算法适用于强噪声环境,能显著提高信噪比。

关键词：语音质量语音增强子空间方法特征值分解语音帧