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ephemeris n.(pl. ephemerides ) 【天文學】天體...

ephemeron

In the stage of the sun and the moon in sight , azimuth of the sun , the earth and the moon in the spacecraft body coordinate system is simulated . combining the simulated azimuth with the ephemeris of the sun and the moon , the state equation and observation equation are modeled . the initial orbital parameters calculated by least square method are used in orbit state equation to predict spacecraft state and to realize autonomous navigation 在日月可見階段,模擬日、地、月敏感器測量信息,即日、地、月在航天器本體坐標系下的方位信息,結合日月星歷,建立狀態方程及觀測方程,通過最小二乘法得到歷元時刻的軌道狀態初始值,將其代入軌道狀態方程進行自主導航。

To sum up , tested and validated by data sets of shenzhou iv unmanned spacecraft and precise orbit ephemeris , the algorithms presented in the thesis can improve orbit accuracy and reduce random noise considerablely . derived conclusions have important value for reference , and lay the firm technological foundation for future applications 總之,經過神舟四號飛船實測數據計算和精密星歷檢驗,表明本文提出的各種定軌方法可以較好的提高定軌精度,減少隨機噪聲,所得出的結論對于實際應用具有重要的參考價值,并為將來的應用奠定了堅實的技術基礎。

Some message described in the thesis , such as the basic structure of gps - oem , the consists of positioning system , the binary format of almanac and ephemeris , the method and the skill of processing orignal data through singlechip , and so on , is very useful for studying gps and its applications in integrated navigation , and re - development on gps - oem 同時亦可與gis (地理信息系統)配套使用,實現在crt上地圖背景下的運動軌跡顯示。第二個產品, gps時鐘/同步系統,利用全球衛星定位gps衛星的標準utc時間,可在全球得到同步的準確時間。設備采用motorola的12通道gpsoem接收機。

The orientation information of the sun , the moon and the earth , together with ephemeris are utilized to develop autonomous navigation algorithm , as well as its realization by dsp hardware 在小樣本觀測數據情況下,研究利用日地月方位信息和日月星歷表進行航天器自主導航以及利用dsp實現航天器自主導航器的技術。

200s ttff - cold ( with current almanac , position , time and ephemeris ) 50s ttff - warm ( with current almanac , position , and time ) Ttff溫啟動典型值50秒(當擁有當前的天歷、位置和時間數據時)

Effect of ephemeris error on the positioning accuracy of double - star positioning system 星歷誤差對雙星定位系統定位精度的影響

American ephemeris and nautical almanac 美國天文年歷和航海年歷