分析比对了GPS单点测速技术与其他已有测波手段的不同,讨论了基于多普勒频移的GPS测速方法,并分析了各类误差对测速精度的影响。分别利用原始多普勒值和导出多普勒值进行了静态测速试验和动态测速试验,将导出多普勒测速结果与RTK(Real T...分析比对了GPS单点测速技术与其他已有测波手段的不同,讨论了基于多普勒频移的GPS测速方法,并分析了各类误差对测速精度的影响。分别利用原始多普勒值和导出多普勒值进行了静态测速试验和动态测速试验,将导出多普勒测速结果与RTK(Real Time Kinematic,实时动态测量系统)位置差分测速进行了比测。结果表明,使用静态数据采用高频导出多普勒值测速的精度可以达到亚厘米级每秒,而采用原始多普勒观测值进行测速因接收机型号的不同,结果差异较大;动态测速试验中,采用导出多普勒测速的方法与RTK位置差分测速的符合精度可达cm/s。展开更多
首先分析比对了已有的测波方法,阐述了将GPS单点测速应用到测波中的优点。然后讨论了基于多普勒频移的测速方法,并分析了各类误差对测速精度的影响。最后利用静态数据进行动态测速模拟试验和实测动态数据测速与RTK(Real Time Kinematic...首先分析比对了已有的测波方法,阐述了将GPS单点测速应用到测波中的优点。然后讨论了基于多普勒频移的测速方法,并分析了各类误差对测速精度的影响。最后利用静态数据进行动态测速模拟试验和实测动态数据测速与RTK(Real Time Kinematic,实时动态测量系统)位置差分测速进行一致性检验。结果表明,使用静态数据采用高频导出多普勒值测速的精度可以达到亚厘米每秒的量级,而采用原始多普勒观测值进行测速因接收机型号的不同,结果差异较大;动态测速试验中,采用导出多普勒测速的方法与RTK位置差分测速的符合精度可达3~15 cm/s。展开更多
A new nonlinear integral transform of ocean wave spectra into Along-Track Interferometric Synthetic Aperture Radar (ATI-SAR) image spectra is described. ATI-SAR phase image spectra are calculated for various sea state...A new nonlinear integral transform of ocean wave spectra into Along-Track Interferometric Synthetic Aperture Radar (ATI-SAR) image spectra is described. ATI-SAR phase image spectra are calculated for various sea states and radar configurations based on the nonlinear integral transform. The numerical simulations show that the slant range to velocity ratio (R/V), significant wave height to ocean wavelength ratio (Hs/λ), the baseline (2B) and incident angle (θ) affect ATI-SAR imaging. The ATI-SAR imaging theory is validated by means of Two X-band, HH-polarized ATI-SAR phase images of ocean waves and eight C-band, HH-polarized ATI-SAR phase image spectra of ocean waves. It is shown that ATI-SAR phase image spectra are in agreement with those calculated by forward mapping in situ directional wave spectra collected simultaneously with available ATI-SAR observations. ATI-SAR spectral correlation coefficients between observed and simulated are greater than 0.6 and are not sensitive to the degree of nonlinearity. However, the ATI-SAR phase image spectral turns towards the range direction, even if the real ocean wave direction is 30°. It is also shown that the ATI-SAR imaging mechanism is significantly affected by the degree of velocity bunching nonlinearity, especially for high values of R/V and Hs/λ.展开更多
基金supported by the Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology(MRE201233)Key Laboratory of Surveying and Mapping Technology on Island and ReefState Bureau of Surveying and Mapping(2012B04)
文摘分析比对了GPS单点测速技术与其他已有测波手段的不同,讨论了基于多普勒频移的GPS测速方法,并分析了各类误差对测速精度的影响。分别利用原始多普勒值和导出多普勒值进行了静态测速试验和动态测速试验,将导出多普勒测速结果与RTK(Real Time Kinematic,实时动态测量系统)位置差分测速进行了比测。结果表明,使用静态数据采用高频导出多普勒值测速的精度可以达到亚厘米级每秒,而采用原始多普勒观测值进行测速因接收机型号的不同,结果差异较大;动态测速试验中,采用导出多普勒测速的方法与RTK位置差分测速的符合精度可达cm/s。
文摘首先分析比对了已有的测波方法,阐述了将GPS单点测速应用到测波中的优点。然后讨论了基于多普勒频移的测速方法,并分析了各类误差对测速精度的影响。最后利用静态数据进行动态测速模拟试验和实测动态数据测速与RTK(Real Time Kinematic,实时动态测量系统)位置差分测速进行一致性检验。结果表明,使用静态数据采用高频导出多普勒值测速的精度可以达到亚厘米每秒的量级,而采用原始多普勒观测值进行测速因接收机型号的不同,结果差异较大;动态测速试验中,采用导出多普勒测速的方法与RTK位置差分测速的符合精度可达3~15 cm/s。
基金Supported by National Natural Science Foundation of China(No.40276050)
文摘A new nonlinear integral transform of ocean wave spectra into Along-Track Interferometric Synthetic Aperture Radar (ATI-SAR) image spectra is described. ATI-SAR phase image spectra are calculated for various sea states and radar configurations based on the nonlinear integral transform. The numerical simulations show that the slant range to velocity ratio (R/V), significant wave height to ocean wavelength ratio (Hs/λ), the baseline (2B) and incident angle (θ) affect ATI-SAR imaging. The ATI-SAR imaging theory is validated by means of Two X-band, HH-polarized ATI-SAR phase images of ocean waves and eight C-band, HH-polarized ATI-SAR phase image spectra of ocean waves. It is shown that ATI-SAR phase image spectra are in agreement with those calculated by forward mapping in situ directional wave spectra collected simultaneously with available ATI-SAR observations. ATI-SAR spectral correlation coefficients between observed and simulated are greater than 0.6 and are not sensitive to the degree of nonlinearity. However, the ATI-SAR phase image spectral turns towards the range direction, even if the real ocean wave direction is 30°. It is also shown that the ATI-SAR imaging mechanism is significantly affected by the degree of velocity bunching nonlinearity, especially for high values of R/V and Hs/λ.