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Measurements and analysis of multistatic and multimodal micro-Doppler signatures for automatic target classification [PDF]
, 2014 The purpose of this paper is to present an experimental trial carried out at the Defence Academy of the United Kingdom to measure simultaneous multistatic and multimodal micro-Doppler signatures of various targets, including humans and flying UAVs ...
Marcio Perassoli +5 more
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地震科学进展, 2021 A magnitude M7.8 earthquake struck Kermadec Island，New Zealand on March 5，2021. In this study we determined surface wave magnitude using 692 stations from USGS global networks and 112 stations from China global earthquake monitoring system，then analyzed ...
Wenze Deng
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Teaching the Doppler effect in astrophysics [PDF]
, 2017 \ud \ud The Doppler effect is a shift in the frequency of waves emitted from an object moving relative to the observer. By observing and analysing the Doppler shift in electromagnetic waves from astronomical objects, astronomers gain greater insight into
Cowley, Michael, Hughes, Stephen W.
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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 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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Acousto-optic frequency switching for single-camera planar Doppler velocimetry [PDF]
, 2001 A single-camera Planar Doppler velocimetry system has been demonstrated, in which illumination beams at two closely-spaced optical frequencies are derived from a single Argon-ion laser.
Nobes, David S. +5 more
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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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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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Modeling of Monopulse Radar Signals Reflected from Ground Clutter in a Time Domain Considering Doppler Effects [PDF]
Journal of Electromagnetic Engineering and Science, 2020 To evaluate the performance of a monopulse radar system, it is necessary to accurately model radar return signals from the ground surface in a time domain.
Jeong-Hun Nam +4 more
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