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A Cooperative MIMO Transmission Scheme for Cluster-based Wireless Sensor Networks

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China Communications 2010年第5期7卷 14-22页

作者： Ding Jie liu danpu Wu Huari Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 P. R. China Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 P. R. China

Wireless sensor network is becoming more and more popular in recent years, but energy- constrained characteristic of sensor nodes is one of the critical issues that we must consider in system design. In this paper, a cluster-based virtual VBLAST transmission scheme is proposed to achieve energy savings for energy-constrained wireless sensor networks. In the proposed scheme, instead of using cluster member as cooperative nodes, multiple cluster heads cooperate to form virtual antenna array so that V-BLAST based virtual MIMO transmission can be implemented. Based on the communication energy consumption model, a way to optimize the parameters for the scheme is given. In addition, detailed simulation is performed to evaluate the performance of the proposed scheme for both densely and sparsely deployed sensor networks. Theoretical analysis and simulation results verify the energy efficiency of the proposed scheme.

关键词： energy efficiency virtual MIMO VBLAST cluster wireless sensor networks

Off-Grid Compressed Channel Estimation with Parallel Interference Cancellation for Millimeter Wave Massive MIMO

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China Communications 2024年第3期21卷 51-65页

作者： liu Jinru Tian Yongqing liu danpu Zhang Zhilong Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and ConvergenceBeijing University of Posts and TelecommunicationsBeijing100876China

Millimeter wave(mmWave)massive multiple-input multiple-output(MIMO)plays an important role in the fifth-generation(5G)mobile communications and beyond wireless communication systems owing to its potential of high ***,channel estimation has become very challenging due to the use of massive MIMO antenna ***,the mmWave channel has strong sparsity in the spatial angle domain,and the compressed sensing technology can be used to convert the original channel matrix into the sparse matrix of discrete angle *** the high-dimensional channel matrix estimation is transformed into a sparse recovery problem with greatly reduced computational ***,the path angle in the actual scene appears randomly and is unlikely to be completely located on the quantization angle grid,thus leading to the problem of power ***,multiple paths with the random distribution of angles will bring about serious interpath interference and further deteriorate the performance of channel *** address these off-grid issues,we propose a parallel interference cancellation assisted multi-grid matching pursuit(PIC-MGMP)algorithm in this *** proposed algorithm consists of three stages,including coarse estimation,refined estimation,and inter-path cyclic iterative inter-ference *** specifically,the angular resolution can be improved by locally refining the grid to reduce power leakage,while the inter-path interference is eliminated by parallel interference cancellation(PIC),and the two together improve the estimation *** results show that compared with the traditional orthogonal matching pursuit(OMP)algorithm,the normalized mean square error(NMSE)of the proposed algorithm decreases by over 14dB in the case of 2 paths.

关键词： channel estimation compressed sensing inter-path interference millimeter wave massive MIMO off-grid parallel interference cancellation

Robust hybrid beamforming design for millimeter-wave massive MIMO systems

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The Journal of China Universities of Posts and Telecommunications 2019年第3期26卷 44-49页

作者： Zhang Kai Xu Guixian Yin Changchuan liu danpu School of Telecommunication Engineering Beijing University of Posts and Telecommunications

Hybrid analog-digital beamforming is recognized as a promising solution for a practical implementation of massive multiple-input multiple-output(MIMO) systems based on millimeter-wave(mmWave) technology. In view of the overwhelming hardware cost and excessive power consumption and the imperfection of the channel state information(CSI), a robust hybrid beamforming design is proposed for the mmWave massive MIMO systems, where the robustness is defined with respect to imperfect knowledge or error of the CSI at the transmitter due to limited feedback and/or imperfect channel estimation. Assuming the errors of the CSI are bounded, the optimal hybrid beamforming design with robustness is formulated to a mean squared error(MSE) minimization problem. An iterative semidefinite programming(SDP) based algorithm is proposed to obtain the beamforming matrices. Simulation results show that the proposed robust design can provide more than 4 dB performance gain compared to that of non-robust design.

关键词： hybrid beamforming imperfect CSI massive MIMO millimeter-wave MSE

Energy-Efficient Transmission Scheme for Mobile Data Gathering in Wireless Sensor Networks

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China Communications 2013年第3期10卷 114-123页

作者：刘丹谱张铠麟丁杰 Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Energy conservation in Wireless Sensor Networks (WSNs) has always been a crucial issue and has received increased attention in the recent years. A transmission scheme for energy-constrained WSNs is proposed in this paper. The scheme, called MIHOP (MIMO and Multi-hop), combines cluster-based virtual MIMO and multi-hop technologies. The multihop mode is employed in transmitting data when the related sensors are located within a specific number of hops from the sink, and the virtual MIMO mode is used in transmitting data from the remaining sensor nodes. We compare the energy consumption of different transmission schemes and propose an algorithm for determining the optimal hop count in MIHOP. A controllable mobile sink that reduces the energy consumed in sensor transmission is also adopted for data collection. The theoretical analysis and the Monte Carlo simulation demonstrate that the proposed scheme significantly outperforms individual virtual MIMO, multi-hop technologies, and double-string networks in terms of energy conservation. The energy consumption levels under the MIHOP scheme are approximately 12.98%, 47.55% and 48.30% less than that under virtual MIMO schemes, multi-hop networks and doublestring networks, respectively.

关键词： wireless sensor networks energyefficiency virtual MIMO multi-hop network mobile sink

WiMAX and Its Applications (3)

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ZTE Communications 2008年第1期6卷 59-62页

作者： liu danpu, Hao Jianjun, Yue Guangxin (Beijing University of Posts and Telecommunications, Beijing 100876, China)

Worldwide Interoperability for Microwave Access (WiMAX), an emerging broadband radio access technology, has attracted much attention from the whole telecom industry in recent years. Its main features are the high-speed transmission rate, large coverage, support for mobility, QoS guarantee and all-IP architecture. The technology fulfills the integration of packetized data, broadband access and mobilized terminal; therefore, it has a bright future for wide application. This lecture discusses WiMAX in four parts, and this part introduces QoS mechanism of the MAC layer and the WiMAX network architecture.

关键词： WiMAX and Its Applications CSN Access MAC

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一种新的最佳多维星座成形算法

通信学报 1998年第10期19卷 13-19页

作者：刘丹谱乐光新北京邮电大学

本文提出一种新的实现对多维星座最佳成形区域—截断多圆柱映射的编码和译码算法，该算法采用循环和移位操作大幅度地减少了存储空间，适合于用数字信号处理器实现。

关键词：多维星座成形算法截断多圆柱编码译码 DSP

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DMT信道上的一种改进的实用比特分配算法

通信学报 1998年第11期19卷 65-70页

作者：刘丹谱乐光新北京邮电大学

本文提出了一种改进的用于ＤＭＴ信道的实用比特分配算法，它可以在整比特数限制下实现近似平坦的功率分布。这种算法与其它算法的性能几乎相等，但是大幅度降低了计算量和运行时间。

关键词：平坦功率分布 DMT调制多载波调制技术

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离散多频信道上的SVQ成形方法

电子学报 1999年第1期27卷 112-114页

作者：刘丹谱乐光新北京邮电大学

本文提出一种在离散多频（ＤＭＴ）调制系统中采用区域分割，依次沿着各子信道进行标量矢量量化器（ＳＶＱ）成形的方法，并对其性能进行了分析和模拟．

关键词：离散多频调制 SVQ成形成形增益连续近似

IPv4 Based Reliable Mobile Multicast Technology

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ZTE Communications 2009年第3期7卷 41-45页

作者： Zhong Qiu,Chen Xiaohua,liu danpu(Beijing University of Posts and Telecommunications,Beijing 100876,P.R.China)

The mobile multicast technology has been a research hotspot in the wireless Internet field in recent *** a large part of its applications requires the reliability in a mobile environment to be equivalent to that provided by wireline ***,the inherent features of a mobile environment,that is,high error rate of links and dynamically changing multicast members’ locations,are great difficulties for mobile multicast,let alone reliable mobile *** IPv4-based reliable mobile multicast algorithms come with two different design philosophies.A part of the algorithms is to be improved for better reliability by solving existing algorithm-related problems;while other algorithms are to implement reliable mobile multicast with new function entities introduced to guarantee reliability.

关键词： MHA IPv4 Based Reliable Mobile Multicast Technology link node MN 移动组播 MFA GFA DMSP