GPS定位数据在海洋一号卫星中的应用与比较

简要介绍了海洋一号卫星星载GPS接收机的定位原理、流程和应用，探讨了一种在轨定位结果的确认和互验方法．借助于卫星工具包软件(STK)，利用NASA网站公布的HY-1卫星两行根数(TLE)进行卫星轨道推算，生成星下点位置，并与相应时刻星载GPS接收机实测数据得到的星下点位置进行比较，由此得到两种方法定位结果之间的偏差，用实际在轨数据验证了两者的位置符合程度．

THE APPLICATION AND COMPARISON OF GPS POSITIONING DATA ON HY-1 SATELLITE

HY-1 Satellite was launched successfully on May 15th, 2002. It is the first ocean color observation satellite in China. On the other hand it is the first long life experimental and operational small satellite in China. The on-board GPS receiver was successfully used in navigation and give out the precise time. The positioning principle, flow chart and application of the GPS receiver on HY-1 satellite are introduced in this paper. A method to confirm and verify the on orbit positioning data is discussed. Using the Two Line Elements (TLE) from NASA web, the satellite orbit is calculated by the Satellite Tool Kit (STK) software so to obtain the nadir positions, then, the real GPS data at that time are processed and converted to the nadir positions. The nadir geodetic positions from GPS data are compared with those from the TLE. The difference of nadir positions between GPS and TLE methods are given. It is very helpful to give the comparison using the real on-board data.