风云四号B星(FY-4B)是中国最新一代的静止轨道气象卫星,其资料具有更高的时空分辨率。为了进一步推进FY-4B云导风资料在数值模式中的应用,以FY-4B云导风资料为主要研究对象,结合FY-4A云导风资料进行对比,首先分析了其观测误差的垂直分...风云四号B星(FY-4B)是中国最新一代的静止轨道气象卫星,其资料具有更高的时空分辨率。为了进一步推进FY-4B云导风资料在数值模式中的应用,以FY-4B云导风资料为主要研究对象,结合FY-4A云导风资料进行对比,首先分析了其观测误差的垂直分布情况,以此更新WRFDA(Weather Research and Forecasting model Data Assimilation system)同化系统中默认观测误差,随后进一步探究了云导风资料同化对2022年台风“梅花”的预报影响。研究结果表明:FY-4B云导风资料U、V分量的观测误差整体上小于FY-4A;同化FY-4A云导风资料后,模拟的台风路径逐渐偏西;而同化FY-4B云导风资料使得台风中心动力场信息更加完善,分析场对流层中高层西风增强,预报的台风路径更接近实况;相较于同化FY-4A云导风资料,同化FY-4B云导风资料对降水预报的改善效果更好。展开更多
Bistatic/multistatic radar has great potential advantages over its monostatic counterpart. However, the separation of a transmitter and a receiver leads to difficulties in locating the target position accurately and g...Bistatic/multistatic radar has great potential advantages over its monostatic counterpart. However, the separation of a transmitter and a receiver leads to difficulties in locating the target position accurately and guaranteeing space-timefrequency synchronization of the transmitter and the receiver.The error model of space-time-frequency synchronization in a motion platform of bistatic/multistatic radar is studied. The relationship between the space synchronization error and the transmitter platform position, receiver platform position, moving state, and beam pointing error, is analyzed. The effect of space synchronization error on target echo power is studied. The target scattering characteristics are restructured by many separate scattering centers of the target in high frequency regions. Based on the scattering centers model of the radar target, this radar target echo model and the simulation method are discussed. The algorithm of bistatic/multistatic radar target echo accurately reflects the scattering characteristics of the radar target, pulse modulation speciality of radar transmitting signals, and spacetime-frequency synchronization error characteristics between the transmitter station and the receiver station. The simulation of bistatic radar is completed in computer, and the results of the simulation validate the feasibility of the method.展开更多
文摘风云四号B星(FY-4B)是中国最新一代的静止轨道气象卫星,其资料具有更高的时空分辨率。为了进一步推进FY-4B云导风资料在数值模式中的应用,以FY-4B云导风资料为主要研究对象,结合FY-4A云导风资料进行对比,首先分析了其观测误差的垂直分布情况,以此更新WRFDA(Weather Research and Forecasting model Data Assimilation system)同化系统中默认观测误差,随后进一步探究了云导风资料同化对2022年台风“梅花”的预报影响。研究结果表明:FY-4B云导风资料U、V分量的观测误差整体上小于FY-4A;同化FY-4A云导风资料后,模拟的台风路径逐渐偏西;而同化FY-4B云导风资料使得台风中心动力场信息更加完善,分析场对流层中高层西风增强,预报的台风路径更接近实况;相较于同化FY-4A云导风资料,同化FY-4B云导风资料对降水预报的改善效果更好。
基金supported by the National Natural Science Foundation of China(61271327)
文摘Bistatic/multistatic radar has great potential advantages over its monostatic counterpart. However, the separation of a transmitter and a receiver leads to difficulties in locating the target position accurately and guaranteeing space-timefrequency synchronization of the transmitter and the receiver.The error model of space-time-frequency synchronization in a motion platform of bistatic/multistatic radar is studied. The relationship between the space synchronization error and the transmitter platform position, receiver platform position, moving state, and beam pointing error, is analyzed. The effect of space synchronization error on target echo power is studied. The target scattering characteristics are restructured by many separate scattering centers of the target in high frequency regions. Based on the scattering centers model of the radar target, this radar target echo model and the simulation method are discussed. The algorithm of bistatic/multistatic radar target echo accurately reflects the scattering characteristics of the radar target, pulse modulation speciality of radar transmitting signals, and spacetime-frequency synchronization error characteristics between the transmitter station and the receiver station. The simulation of bistatic radar is completed in computer, and the results of the simulation validate the feasibility of the method.
