Orbit Determination of the MIR Space using MOMSNAV GPS Measurements

As part of the MOMSNAV package, a Motorola 12 channel C/A code GPS receiver will be flown aboard the Priroda module of the MIR space station in mid 1996. Despite their limited accuracy, the (X,Y,Z) coordinates determined by the receiver provide a high potential for fast and simple orbit reconstruction and prediction, when treated as measurements within an orbit determination soft- ware. Since spacebased measurements are not currently available due to multiple Launch delays of the Priroda module, groundbased hardware-in-the-loop simulations have been used to assess the error spectrum of the GPS position solutions and the accuracy of the resulting orbit determination. The least-square adjustment of GPS C/A position data is discussed for the case of precision numerical orbit models as well as NORAD twoline element models.The results obtained encourage the use of GPS as a simple tracking devicefor routine orbit dermination and prediction of low-earth satellites.