iGage iG5, Руководство пользователя

Страница: 57 / 96

57 iG5 User Manual
A smart rule-of-thumb is to try to never collect observation
data that spans midnight UTC. It causes additional problems a
few days after collection when OPUS is forced to splice ultra-
rapid and rapid orbits. It causes additional problems in a few
weeks if precise orbits become available for only the 1
st
portion of an occupation and OPUS has to splice precise
orbits for the first portion and rapid orbits for the second
portion.
#6 Offline CORS Stations
Often when you look at the ‘Data Availability’ plot from a
CORS station’s information page:
You will sometimes find that several hours or an entire day’s
observation data is unavailable, shown as gray instead of
blue.
For a station to be used in a solution, overlapping data for the
ENTIRE user occupation must exist. So if you performed an
observation on Julian day 117 near the station PUC2 (shown
above) and were planning on having PUC2 data available,
then you are out of luck.
#7 NGS CORS Station Quality
When you submit an occupation from your receiver, your
receiver’s recorded data is compared with the recorded data
from nearby surrounding CORS stations.