In this paper, first there is a brief introduction about GPS
positioning and timing principle. Then there is a data collection
through Superstar-II receiver and a simulation of GPS
positioning and timing module. According to the results of GPS
positioning simulation, we can know that they meet basically
the requirements of single-point positioning. In addition, by the
data analysis of timing simulation’s results, we can know that
the UTC time is calculated by Julian Day which is converted
into GPS time without correcting error for the current moment
time received by the receiver. Therefore, after a rough
calculation of calendar time through Julian Day converted from
GPS time, we calculate precise leap seconds through UTC
parameters to correct the calendar time converted directly from
GPS time, which makes the accuracy of time reach the
precision we needed. Based on this it will play an important
role do great help in deeply studying timing accuracy.