搜索结果: 16-30 共查到“理学 GNSS”相关记录31条 . 查询时间(0.149 秒)
随着电子与通讯等现代科技手段的飞速发展，许多卫星技术的研究和应用日益广泛，而这些研究与应用跟大气对无线电波传播的影响密切相关。地球电离层是空间天气的主要组成部分之一，它的活动和特性直接影响到无线电通信、卫星精密导航定位、无线电技术的航天测控等技术领域。
The sensitivity of GNSS measurements in Fennoscandia to distinct three-dimensional upper-mantle structures
GNSS measurements Fennoscandia three-dimensional upper-mantle structures
2015/1/6
The sensitivity of global navigation satellite system (GNSS) measurements in Fennoscandia to nearby viscosity variations in the upper mantle is investigated using a 3-D finite element model of glacial...
Simulations of direct and reflected wave trajectories for ground-based GNSS-R experiments
Simulations of direct refl ected wave trajectories
2014/12/19
The detection of Global Navigation Satellite System (GNSS) signals that are reflected off the surface, along
with the reception of direct GNSS signals, offers a unique
opportunity to monitor w...
高频GNSS形变波的震相识别：模拟实验与实例分析
实时高频GNSS形变波 振动台模拟实验 强震震例 震相分析 震相识别
2014/10/8
高频GNSS震时形变波震相及识别是GNSS地震学的重要内容.在实时数据处理基础上，本文利用振动台的高频GNSS观测实验，并结合近期部分大震的高频GNSS形变波震相特征进行研究.数据处理结果表明，实时处理与事后处理的精度在同一量级，且与采样率无关.通过与同址观测强震仪和地震计记录的对比及特定震相的频谱分析，发现高频GNSS可完整记录P波、S波、Love波及Rayleigh波震相，影响震相记录的主要因...
实时GNSS地震仪系统实现及精度分析
GNSS地震仪 实时精密单点定位 PANDA软件 海啸预警
2013/11/1
高频GNSS数据实时精密单点定位(RTPPP)可实时获得地表瞬时动态形变和地震波信号,为地震参数快速确定、地震快速响应及海啸预警提供实时的观测资料.本文构建了实时GNSS地震仪系统,主要包括RTPPP和实时探测两部分.利用RTPPP 方法处理了模拟的震动实验平台实验数据和2010年Baja California地震的数据,并与惯导(IMU)、事后PPP和差分相对定位结果比较,定量评估了实时GNSS...
GNSS-R测量地表土壤湿度的地基实验
GNSS-R 土壤湿度 地基实验 土壤介电常数
2011/11/22
应用地基GNSS-R测量土壤湿度,相比空基而言,反射信号接收天线安装位置低,反射区面积小,反射区域内土壤构成成分一致,可以克服空基实验带来的反射区面积大、反射区内土壤地貌复杂的因素,有利于提高反演的精度.本文介绍了地基GNSS-R反演土壤湿度的原理和方法.首先通过归一化处理消除电离层和中性大气对信号强度的影响,然后利用光滑地表散射模型和土壤介电常数模型反演土壤湿度.为验证GNSS-R反演结果的精度...
Influence of Doppler Bin Width on GNSS Detection Probabilities
GNSS acquisition Doppler bin width receiver operating characteristics
2011/9/1
Abstract: The acquisition stage in GNSS receivers determines Doppler shifts and code phases of visible satellites. Acquisition is thus a search in two continuous dimensions, where the digital algorith...
The use of products from ground-based GNSS observations in meteorological nowcasting
The use products from ground-based GNSS observations meteorological nowcasting
2010/9/10
Convective rainfall is often focalized in areas of moisture convergence. A close relationship between precipitation and fast variations of vertically-integrated water vapour (IWV) has been found in nu...
基于GNSS网络的实时精密单点定位及精度分析
实时精密单点定位 GNSS网络 历元间差分
2010/12/27
基于局域GNSS网络，以历元间、星间差分技术实时估计了GPS卫星相对钟差的历元间差值；针对所估计实时精密钟差的特征，推导了实时精密单点定位的估计模型.对所估计得到的相对钟差的历元间差值、实时定位结果分别进行了比较、分析.结果表明，相对钟差的历元间差值与IGS的最终星历相比其精度可以达到0.08 ns；每小时观测的实时静态定位结果在N、E、U三个方向的精度分别为1.47、3.62、4.09 cm.动...
Simulation of space-borne tsunami detection using GNSS-Reflectometry applied to tsunamis in the Indian Ocean
Simulation space-borne tsunami detection GNSS-Reflectometry applied tsunamis the Indian Ocean
2010/10/20
Within the German-Indonesian Tsunami Early Warning System project GITEWS (Rudloff et al., 2009), a feasibility study on a future tsunami detection system from space has been carried out. The Global Na...
Preliminary results of land subsidence monitoring project in Konya Closed Basin between 2006–2009 by means of GNSS observations
Preliminary results land subsidence monitoring project Konya Closed Basin
2010/10/20
One of the potential dangers that might arise as a result of bringing excessive amounts of groundwater to the surface of the Earth is land subsidence. Such surface deformations – these velocities may ...
探讨了GNSS系统中，伪码跟踪环的时间鉴别力与采样率之间的定量关系，提出了时间鉴别力的性能评估准则及其计算方法。然后以GPS L5信号为例，重点考察多普勒效应对采样系统时间鉴别力的影响。实验表明，一般来说，随着采样率的增加，采样系统的时间鉴别力也会随之提高。但是当采样率接近或者恰好等于码片速率的整数倍时，采样系统的时间鉴别力会陡然下降。虽然多普勒效应能够显著改善等量采样系统的时间鉴别力，但是与设计...
Temperature and Water Vapour Profiling by Carrier Phase GNSS
radiosonde GNSS water vapour temperature profiling
2009/6/9
We propose precise, physically absolute temperature profiling based on use of radiosonde GNSS
carrier phase measurements. This contribution provides some theory development, especially on error propa...
INVESTIGATING ADJUSTMENT OF AIRBORNE LASER SCANNING STRIPS WITHOUT USAGE OF GNSS/IMU TRAJECTORY DATA
Airborne Laser Scanning adjustment LIDAR georeferencing quality control
2016/2/29
Airborne laser scanning (ALS) requires GNSS (Global Navigation Satellite System; e.g. GPS) and an IMU (Inertial Measurement
Unit) for determining the dynamically changing orientation of the scanning ...
必须加速发展基于GNSS的CNS/ATM系统（图）
GNSS CNS/ATM系统 导航 通信 发展 交通管理
2005/8/1
本文从传统的陆基系统的局限性入手，侧重述及加速发展新航行系统的必然性与显著的效益及其业已具备的技术基础，同时阐述了系统构成及其工作原理，并对系统特点作了简单地分析。