In this study, the precise orbit determination (POD) software is developed for
optical observation. To improve the performance of the estimation algorithm, a nonlinear
batch filter, based on the unscented transform (UT) that overcomes the disadvantages of
the least-squares (LS) batch filter, is utilized. The LS and UT batch filter algorithms
are verified through numerical simulation analysis using artificial optical
measurements. We use the real optical observation data of a low Earth orbit (LEO)
satellite, Cryosat-2, observed from optical wide-field patrol network (OWL-Net), to
verify the performance of the POD software developed. The effects of light travel time,
annual aberration, and diurnal aberration are considered as error models to correct
OWL-Net data. As a result of POD, measurement residual and estimated state vector of the
LS batch filter converge to the local minimum when the initial orbit error is large or
the initial covariance matrix is smaller than the initial error level. However, UT batch
filter converges to the global minimum, irrespective of the initial orbit error and the
initial covariance matrix.