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A 5.4mW Low-Noise High-Gain CMOS RF Front-End Circuit for Portable GPS receivers

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Journal of Semiconductors 2008年第10期29卷 1963-1967页

作者：王良坤马成炎叶甜春中国科学院微电子研究所北京100029 杭州中科微电子有限公司杭州310053

This paper describes a CMOS low noise amplifier （LNA） plus the quadrature mixers intended for use in the front-end of portable global positioning system （GPS） receivers. The LNA makes use of an inductively degenerated input stage and power-constrained simultaneous noise and input matching techniques. The quadrature mixers are based on a Gil- bert cell type. The circuits are implemented in a TSMC 0.18μm RF CMOS process. Measurement results show that a voltage conversion gain of 35dB is achieved with a cascade noise and an input return loss of - 22.3dB. The fully differential figure of 2.4dB,an input ldB compression point of - 22dBm, circuits only draw 5.4mW from a 1.8V supply.

关键词： CMOS RF IC GPS low-noise amplifiers mixers receivers noise figure

The usability of GNSS mass-market receivers for cadastral surveys considering RTK and NRTK techniques

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Geodesy and Geodynamics 2019年第4期10卷 282-289页

作者： Paolo Dabove Politecnico di Torino Geomatics Group Department of Environment Land and Infrastructure Engineering

Nowadays many positioning techniques and methods are applied to the cadastral surveys. Starting from last decade, GPS/GNSS positioning had become one of the most used methodology thanks to the rapid development of satellite-based positioning and to the appearance of GNSS mass-market receivers and antennas. Methods based on these instruments are more affordable than the conventional ones even if their use for precise positioning is not so intuitive. This study is aimed to evaluate the use of singlefrequency GPS/GNSS mass-market receivers for cadastral surveys, considering both single-base RealTime Kinematic(RTK) and Network Real-Time Kinematic(NRTK) methodologies. Furthermore, a particular tool for predicting and estimating the occurrence of false fix of the phase ambiguities has been considered, in order to improve the accuracy and precision of the solutions. Considering the single-base positioning, the research results showed the difference of a few centimetres between the reference coordinates and the estimated ones if the distance between master and rover is less than 3 km, while considering the network positioning and the Virtual Reference Station correction, the difference are about a couple of centimetres for East and North component, and about 5 cm for the Up.

关键词： GNSS Cadastral surveying RTK NRTK positioning Mass-market receivers

Mode demultiplexing hybrids for mode-division multiplexing coherent receivers

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Photonics Research 2019年第8期7卷 917-925页

作者： HE WEN HUIYUAN LIU YUANHANG ZHANG PENG ZHANG GUIFANG LI CREOL The College of Optics&PhotonicsUniversity of Central FloridaOrlandoFlorida32816-2700USA Changchun University of Science and Technology Changchun130012China

We propose a mode demultiplexing hybrid(MDH) that integrates mode demultiplexing, local oscillator power splitting, and optical 90-deg mixing using multi-plane light conversion(MPLC). We demonstrate the realization of a three-mode MDH using four phase plates, one more than what is required for an MPLC-based mode demultiplexer, via numerical simulations. The performance of the three-mode MDH is comparable to that of commercial single-mode 90-deg hybrids. This multiple-functionality device enables simplification of the coherent optical front end of mode-division multiplexing receivers.

关键词： domain Mode demultiplexing mode-division multiplexing coherent receivers

Analysis of Multipath and CW Interference Effects on GNSS receivers with EMLP Discriminator

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Communications and Network 2013年第3期5卷 80-85页

作者： Bo Qu Jiaolong Wei Shuangna Zhang Liang Bi Department of Electronic and Information Engineering Huazhong University of Science and Technology China Space Star Technology Co. Ltd China

Multipath and continuous wave (CW) interference may cause severe performance degradation of global navigation satellite system (GNSS) receivers. This paper analyzes the code tracking performance of early-minus-late power (EMLP) discriminator of GNSS receivers in the presence of multipath and CW interference. An analytical expression of the code tracking error is suggested for EMLP discriminator, and it can be used to assess the effect of multipath and CW interference. The derived expression shows that the combined effects include three components: multipath component;CW interference component and the combined component of multipath and CW interference. The effect of these components depends on some factors which can be classified into two categories: the receiving environment and the receiver parameters. Numerical results show how these factors affect the tracking performances. It is shown that the proper receiver parameters can suppress the combined effects of multipath and CW interference.

关键词： Analysis of Multipath and CW Interference Effects on GNSS receivers with EMLP Discriminator

New Strategy of Collaborative Acquisition for Connected GNSS receivers in Deep Urban Environments

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Positioning 2018年第3期9卷 23-46页

作者： Maherizo Andrianarison Mohamed Sahmoudi René Jr. Landry LASSENA Laboratory Ecole de Technologie Supérieure Montreal Canada ISAE-SUPAERO & TESA University of Toulouse Toulouse France

Collaborative Positioning (CP) is a better localization technique used to locate a user in challenged environments, which is driven by the increasing presence of cellular phones and mobile devices in urban areas. The basic idea is that the mobile devices can cooperate with each other to improve their ability to determine their position. In this concept, a network of GNSS (Global Navigation Satellite System) receivers can collectively receive available satellite signals, and each receiver can receive signal measurements from other receivers via a communication link. This work shows how to use the Collective Detection (CD) approach to deal with the concept of collaborative or cooperative positioning. Specifically, this paper develops a new strategy allowing a receiver in deep urban environment to locate using the CD approach, while overcoming the implementation complexity problem. The idea consists in applying the CD approach in the case of multiple GNSS receivers to assist a receiver in a difficult situation. A typical case of two connected receivers assisting a receiver in difficulty in a deep urban area shows the effectiveness of this strategy. This strategy is tested with real GNSS signals to analyze its feasibility. The overall gain in complexity can reach up to 46% of what has been achieved in previous works.

关键词： Collective Detection Collaborative Positioning Connected GNSS receivers Deep Urban Environments

Link Prediction Method Fusion with Local Structural Entropy for Directed Network

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Chinese Journal of Electronics 2024年第1期33卷 204-216页

作者： Shuxin LIU Hongchang CHEN Lan WU Kai WANG Xing LI People’s Liberation Army Strategic Support Force Information Engineering University

Link prediction utilizes accessible network information to complement or predict the network *** is an important prerequisite for link prediction which means links more likely occurs between two similar nodes. Existing methods utilize the similarity of nodes but neglect of network structure. However the link direction leads to a far more complex structure and contains more information useful than the undirected networks. Most classic methods are difficult to depict the distribution of the network structure with incidental direction so the similarity characteristics of the network structure itself are lost. In this respect, a new method of local structure entropy is proposed to depict the directed structural distribution characteristics, which can be used to evaluate the degree of local structural similarity of nodes and then applied to link prediction methods. Experimental results on 8 real directed networks show that this method is effective for both area under the receiver operating characteristic curve(AUC)and ranking-score measures, and improved predictive capacity of the baseline methodology.

关键词： Correlation Current measurement Area measurement Prediction methods receivers Benchmark testing Entropy

Joint Transmit and Reflective Beamforming Design for Active IRS-Aided SWIPT Systems

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Chinese Journal of Electronics 2024年第2期33卷 536-548页

作者： Weiping SHI Qingqing WU Di WU Feng SHU Jiangzhou WANG School of Electronic and Optical Engineering Nanjing University of Science and Technology Department of Electronic Engineering Shanghai Jiao Tong University School of Information and Communication Engineering Hainan University Department of Automation Shanghai Jiao Tong University School of Engineering University of Kent

To further improve the performance of passive intelligent reflecting surface(IRS)-assisted communication systems and mitigate the serious path loss due to “double-fading ” of IRS-assisted links, an active IRS-aided simultaneous wireless information and power transfer(SWIPT) system is investigated. This paper jointly optimizes the transmit beamforming at the base station(BS) and the phase shifts at the active IRS in order to maximize the power collected by the energy harvesting receiver under both perfect and imperfect channel state information(CSI)states, subject to the signal-to-interference-noise ratio constraint of the information decoding receiver, and the power constraints of the BS/IRS. Under perfect CSI, the alternating optimization algorithm is utilized for obtaining the transmit beamforming at the BS and the phase shifts at the active IRS. For each subproblem, we first transform nonconvex objective function and constraints into convex ones by performing a first-order Taylor expansion. Then, each subproblem is solved by using the interior point method. Given that obtaining perfect CSI is impractical, two robust beamforming designs are proposed for imperfect CSI case. Under the bounded CSI error model, we first transform the non-convex optimization problem into two semidefinite programming subproblems, and then solve each subproblem based on S-procedure and sequential rank-one constraint relaxation(SROCR) techniques. Under the stochastic CSI error model, the alternating optimization method is applied in an iterative manner based on Bernstein-type inequality and SROCR technique. Simulation results show that both robust and non-robust schemes for active IRS-assisted SWIPT systems can achieve extremely superior performance over conventional passive IRS-assisted systems under the same overall power budget.

关键词： Wireless communication Semidefinite programming Array signal processing Simulation Stochastic processes Transforms receivers

A Novel Approach of Electromagnetic Compatibility Conducted Susceptibility Analysis Based on Gaussian Even Pulse Signal

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Chinese Journal of Electronics 2024年第2期33卷 472-478页

作者： Youwei MENG Yanhua PENG Haoyang ZHANG Lilin LI Donglin SU The School of Electronic and Information Engineering Beihang University The Institute of Electromagnetic Compatibility Technology Beihang University The Research Institute for Frontier Science Beihang University

The purpose of the electromagnetic compatibility conducted susceptibility test for interconnected cables in the system is to evaluate its ability to operate acceptably when subjected to interference. We propose a novel conducted susceptibility analysis approach: by injecting the Gaussian even pulse signal, we find that the susceptibility threshold of the system shows two different patterns with the change of signal parameters; then we locate the cause of the susceptibility of the device by analyzing the threshold level curves. The effectiveness of the proposed approach is verified by testing with devices containing digital modules such as navigation receivers. The proposed approach facilitates a deeper understanding of the susceptibility mechanism of systems and their appropriate electromagnetic compatibility design.

关键词： Analytical models Navigation Interference receivers Electromagnetic compatibility Physical layer Time-domain analysis

Cellular V2X-Based Integrated Sensing and Communication System:Feasibility and Performance Analysis

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Chinese Journal of Electronics 2024年第4期33卷 1104-1116页

作者： Yibo LI Junhui ZHAO Jieyu LIAO Fajin HU School of Electronic and Information Engineering Beijing Jiaotong University

Communication and sensing are basically required in intelligent transportation. The combination of two functions can provide a viable way in alleviating concerns about resource limitations. To achieve this, we propose an integrated sensing and communication(ISAC) system based on cellular vehicle-to-everything(C-V2X). We first analyze the feasibility of new radio(NR) waveform for ISAC system. We discuss the possibility of reusing NR waveform for sensing based on current NR-V2X standards. Ambiguity function is calculated to investigate the sensing performance limitation of NR waveform. A C-V2X-based ISAC system is then designed to realize the two tasks in vehicular network simultaneously. We formulate an integrated framework of vehicular communication and automotive sensing using the already-existing NR-V2X network. Based on the proposed ISAC framework, we develop a receiver algorithm for target detection/estimation and communication with minor modifications. We evaluate the performance of the proposed ISAC system with communication throughput, detection probability, and range/velocity estimation *** show that the proposed system achieves high reliability communication with 99.9999% throughput and high accuracy sensing with errors below 1 m and 1 m/s in vehicle scenarios.

关键词： Accuracy Estimation receivers Reliability theory Integrated sensing and communication Throughput Task analysis