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Time-frequency doubly selective channel estimation based on compressed sensing
上海师范大学学报. 自然科学版, 2017 In this paper,considering time-frequency doubly selective channel,we utilize the channel's time correlation that the channel coefficientscorresponding tothe neighboring instants have a strong correlation.And we present a linear approximation method,which
Tu Yuliang +3 more
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Metrology and Measurement Systems, 2020 The possibilities to improve values of the satellite orbit elements by employing the pseudo-ranges and differences of carrier phase frequencies measured at many reference GPS stations are analysed. An improvement of orbit ephemeris is achieved by solving
Skeivalas Jonas +3 more
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Performance analysis of DSSS- and CSS-based physical layer for IoT transmission over LEO satellites
ETRI Journal, 2022 To determine a suitable waveform for Internet of Things (IoT) transmission over low-Earth orbit (LEO) satellites, this paper reports the results of a performance comparison between chirp spread spectrum (CSS)-based LoRa and direct sequence spread ...
Sooyeob Jung +5 more
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Dizhen xuebao, 2018 本文介绍了全球主要地震机构对2008年5月12日汶川地震参数的速报和修订情况，分析了美国地质调查局国家地震信息中心测定的面波震级。通过对比198个全球地震台站测定的面波震级和面波周期，得出如下结论：测定面波震级偏大的台站主要分布在震中的东北方向，测定面波震级偏小的台站主要分布在震中的西南和东南方向，面波周期偏小的台站主要分布在震中东北方向。由于此次地震破裂方向是以北东向单侧破裂为主，且地震多普勒效应导致震中东北方向振动加强，因此该方向上的面波震级偏大，地震烈度衰减慢；而震中西南方向的振动减弱 ...
Ruifeng Liu, Liye Zou, Liwen Zhang
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Performance Evaluation of OTFS-NOMA Scheme for High Mobility Users
Sakarya University Journal of Computer and Information Sciences, 2023 Orthogonal Time Frequency Space (OTFS) is a promising approach which is widely employed in sixth generation (6G) wireless network systems. Because of its superior performance in high-mobility environments, OTFS modulation has received a lot of attention ...
Arif Başgümüş +2 more
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Lightweight and secure vehicle track verification scheme via broadcast communication channels
网络与信息安全学报, 2023 In intelligent transportation systems, it is crucial for smart vehicles to broadcast real-time vehicle track messages to coordinate driving decisions and ensure driving safety.However, attackers can manipulate vehicle tracks by modifying timestamps or ...
Zhiqiang NING, Yuanyuan WANG, Chi ZHANG, Lingbo WEI, Nenghai YU, Yue HAO
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Guidelines for ultrasound examination in ophthalmology. Part III: Color Doppler ultrasonography
Journal of Ultrasonography, 2019 The aim of this article was to present the possibilities of use and application of color-coded Doppler ultrasonography in the diagnosis of various diseases of the eyeball and orbit which result from vascular disorders. Color-coded Doppler ultrasonography
Monika Modrzejewska
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On the Doppler Effect in a Medium
, 1963 This research was supported by the U. S. Air Force through the Air Force Office of Scientific Research of the Air Research and Development Command, under Contract No. AF49(638)-1266. Reproduction in whole or in part is permitted for any purpose of the United States Government. The author is grateful to Professor C. H. Papas for his continued guidance
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High-sensitive acquisition method of GPS signal based on iridium assistance
The Journal of Engineering, 2019 Global positioning system (GPS) signal is severely attenuated in indoor, urban, and forest environments. To capture weak GPS signal, long-time coherent integration and non-coherent integration are used to increase signal to noise ratio (SNR).
Hao Zihuan, Zhang Lei
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