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A survey on one-bit compressed sensing： theory and applications

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Frontiers of Computer Science 2018年第2期12卷 217-230页

作者： Zhilin LI Wenbo XU Xiaobo ZHANG Jiaru LIN Key lab of Universal Wireless communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In the past few decades, with the growing popularity of compressed sensing （CS） in the signal processing field, the quantization step in CS has received significant attention. Current research generally considers multi-bit quantization. For systems employing quantization with a sufficient number of bits, a sparse signal can be reliably recovered using various CS reconstruction algorithms. Recently, many researchers have begun studying the one- bit quantization case for CS. As an extreme case of CS, one- bit CS preserves only the sign information of measurements, which reduces storage costs and hardware complexity. By treating one-bit measurements as sign constraints, it has been shown that sparse signals can be recovered using certain reconstruction algorithms with a high probability. Based on the merits of one-bit CS, it has been widely applied to many fields, such as radar, source location, spectrum sensing, and wireless sensing network. In this paper, the characteristics of one-bit CS and related works are reviewed. First, the framework of one-bit CS is introduced. Next, we summarize existing reconstruction algorithms. Additionally, some extensions and practical applications of one-bit CS are categorized and discussed. Finally, our conclusions and the further research topics are summarized.

关键词： compressed sensing one-bit quantization sign information support consistency

New sets of low-hit-zone frequency-hopping sequence with optimal maximum periodic partial Hamming correlation

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Science China(Information Sciences) 2015年第12期58卷 162-176页

作者： WANG ChangYuan PENG DaiYuan HAN HongYu ZHOU LiMengNan Provincial Key lab of Information Coding and Transmission Institute of Mobile CommunicationsSouthwest Jiaotong University

Recently, Chung et al. gave a general method to construct frequency-hopping sequence set(FHS set) with low-hit-zone(LHZ FHS set) by the Cartesian product. In their paper, Theorems 5 and 8 claim that k FHS sets whose maximum periodic Hamming correlation is 0 at the origin result in an LHZ FHS set based on the Cartesian product, and Proposition 4 presented an upper bound of the maximum periodic Hamming correlation of FHSs. However, their statements are imperfect or incorrect. In this paper, we give counterexamples and make corrections to them. Furthermore, based on the Cartesian product, we construct two classes of LHZ FHS sets with optimal maximum periodic partial Hamming correlation property. It is shown that new FHS sets are optimal by the maximum periodic partial Hamming correlation bound of LHZ FHS set.

关键词： frequency-hopping sequence maximum periodic partial Hamming correlation maximum periodic Hamming correlation low-hit-zone cartesian product

A General Channel Model for Visible Light communications in Underground Mines

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China communications 2018年第9期15卷 95-105页

作者： Jia Wang Ahmed Al-Kinani Wensheng Zhang Cheng-Xiang Wang Li Zhou Shandong Provincial Key lab of Wireless Communication Technologies Shandong University Technical Affairs Department Iraqi Ministry of Communications State Key laboratory of Mobile communications Southeast University

In underground mines, visible light communication(VLC) system is a promising method to realize effective communication,which supports communication and illumination at the same time. Therefore, adequate research of underlying physical propagation phenomenon should be carried out to realize VLC system in underground mines. To design VLC system and evaluate its performance, accurate and efficient channel models, including large-scale fading and scattering characteristics, are needed to be established. However,the characteristics of the underlying VLC channels about fading and scattering have not been sufficiently investigated yet. In this paper, a path loss channel model, based on the recursive model, is proposed precisely. Its path loss exponent is determined by three different trajectories, which is studied in the mining roadway and working face environment. Besides, the shadowing effect for VLC has been modelled by a Bimodal Gaussian distribution in underground mines. Considering the number of transmitters in line-of-sight(Lo S) as well as non-line-of-sight(NLo S) scenarios,our simulation illustrates the fact that, as the curve fitting technique is employed, the path loss displays a linear behavior in *** path loss expression is derived, it is related to the distance. Finally, root mean square(RMS) delay spread and Mie scattering in underground mines are analyzed.

关键词： underground mines visible light communications channel modeling path loss shadowing delay spread.

A quasi-vector finite difference mode solver for optical waveguides with step-index profiles

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Chinese Optics Letters 2006年第5期4卷 285-288页

作者：肖金标张明德孙小菡 lab of Photonics and Optical communications Department of Electronic EngineeringSoutheast UniversityNanjing 210096

A finite difference scheme based on the polynomial interpolation is constructed to solve the quasi-vector equations for optical waveguides with step-index profiles. The discontinuities of the normal components of the electric field across abrupt dielectric interfaces are taken into account. The numerical results include the polarization effects, but the memory requirement is the same as in solving the scalar wave equation. Moreover, the proposed finite difference scheme can be applied to both uniform and non-uniform mesh grids. The modal propagation constants and field distributions for a buried rectangular waveguide and a rib waveguide are presented. Solutions are compared favorably with those obtained by the numerical approaches published earlier.

关键词： Electric fields Finite difference method Interpolation Numerical analysis Rectangular waveguides Vectors

Spacing-adjustable and wavelength-tunable multiwavelength fibre laser with nonlinear Brillouin gain and birefringence fibre loop mirror

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Chinese Physics B 2010年第6期19卷 339-343页

作者：张祖兴伍剑徐坤洪小斌林金桐 Key laboratory of Information Photonics and Optical communications of Ministry of Education Beijing University of Posts and Telecommunications College of Physics & Communication Electronics Key Lab of Photoelectron and Communications of Jiangxi Province Jiangxi Normal University

This paper demonstrates a room-temperature multiwavelength fibre laser with spacing-adjustability and wavelength-tunability. The nonlinear gain of self-excited stimulated Brillouin scattering can suppress mode competition induced by homogeneous broadening of Erbium-doped fibre. With the use of a birefringence fibre loop filter, the wavelength spacing can be adjusted by changing the length of the used birefringence fibre, and the lasing wavelengths can be finely tuned through modifying the filtering profile of the birefringence filter. Multiwavelength output with spectral spacing as small as 0.076 nm and a wavelength number of more than 80 has been successfully produced.

关键词： multiwavelength fibre laser stimulated Brillouin scattering birefringence fibre loop mirror

Interference aware routing for mobile ad hoc networks based on node's sending and receiving capabilities

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 73-79,111页

作者： GU Chao ZHU Qi Jiangsu Key laboratory of Wireless communications Nanjing University of Posts and Telecommunications Key lab on Wideband Wireless communications and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications

How to efficiently build routes among nodes is increasing important for mobile ad hoc networks （MANETs）. This paper puts forward an interference aware routing protocol called Interference aware cross layer routing protocol （IA-CLR） for MANETs based on the IEEE 802.11 medium access layer （MAC）. By defining the node＇s sending and receiving capabilities, IA-CLR can indicate the interference strength of the link in a real and comprehensive way. Further more, in order to choose the route with minimum bottleneck link interference, a new routing metric is proposed by combining the MAC layer and the network layer for cross layer design. Simulation results show that IA-CLR can significantly improve the performances of network such as the average end-to-end delay, the packets loss ratio and the throughput.

关键词： ad hoc networks routing protocol routing design interference aware

Cooperative communications with hierarchical modulation in downlink OFDMA based cellular networks

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Journal of Harbin Institute of Technology(New Series) 2011年第6期18卷 143-148页

作者：张海龙纪红李曦张琳 Key lab of Universal Wireless communications Ministry of EducationBeijing University of Posts and Telecommunications

Cooperative transmission is a promising way to improve system performance in orthogonal frequency division multiple access (OFDMA) based cellular *** paper proposes two heuristic cooperation schemes including relay selection and resource allocation using hierarchical modulation (HM) to fully exploit the radio resources in cellular networks where user equipments (UEs) relay for each *** relay selection procedure considers both the channel conditions and the energies left in relays to make the cooperative communications behave *** mitigate the spectrum efficiency loss due to the half-duplex mode,the bits of relayaided UE and its relay (which is also a UE) are transmitted simultaneously in one sub-channel using HM to improve the utilization efficiency of ***,time resources are used effectively with the adaptively changed proportion of the two sub-frames divided for relay *** results show that the proposed schemes can improve the spectrum efficiency compared with the traditional schemes.

关键词： cooperative communications hierarchical modulation half-duplex spectrum efficiency orthogonal frequency division multiple access (OFDMA)

Low Complexity Joint Hybrid Precoding for Millimeter Wave MIMO Systems

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China communications 2019年第2期16卷 49-58页

作者： Mingyang Cui Weixia Zou Key lab of Universal Wireless communications MOEBeijing University of Posts and Telecommunications State Key lab.of Millimeter Waves Southeast University

In millimeter wave(mmWave) multiple-input multiple-output(MIMO) systems, hybrid precoding has been widely used to overcome the severe propagation loss. In order to improve the spectrum efficiency with low complexity, we propose a joint hybrid precoding algorithm for single-user mmWave MIMO systems in this paper. By using the concept of equivalent channel, the proposed algorithm skillfully utilizes the idea of alternating optimization to complete the design of RF precoder and combiner. Then, the baseband precoder and combiner are computed by calculating the singular value decomposition of the equivalent channel. Simulation results demonstrate that the proposed algorithm can achieve satisfactory performance with quite low complexity. Moreover, we investigate the effects of quantization on the analog components and find that the proposed scheme is effective even with coarse quantization.

关键词： millimeter wave MIMO 5G joint hybrid precoding low complexity

Hybrid Precoder and Combiner Design with Finite Resolution PSs for mmWave MIMO Systems

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China communications 2019年第2期16卷 95-104页

作者： Ran Zhang Weixia Zou Ye Wang Mingyang Cui Key lab of Universal Wireless communications MOEBeijing University of Posts and Telecommunications State Key lab.of Millimeter Waves Southeast University

Hybrid precoding and combining have been considered as a promising technology, which can provide a compromise between hardware complexity and system performance in millimeter wave multiple-input multiple-output systems. However, most existing hybrid precoder and combiner designs generally assume that infinite resolution phase shifters(PSs) are used to produce the analog beamformers. In a practical scene, the design with accurate PSs can lead to high hardware cost and power consumption. In this paper, we investigate the hybrid precoder and combiner design with finite resolution PSs in millimeter wave systems. We employ alternate optimization as the main strategy to jointly design analog precoder and combiner. In addition, we propose a low complexity algorithm, where the analog beamformers are implemented only by finite resolution PSs to maximize spectral efficiency. Then, the digital precoder and combiner are designed based on the obtained analog beamformers to improve the spectral efficiency. Finally, simulation results and mathematical analysis show that the proposed algorithm with low-resolution PSs can achieve near-optimal performance and have low complexity.

关键词： millimeter wave multiple-input multiple-output finite resolution phase shifters hybrid precoding alternate optimization