ashtech HDS800, Справочное руководство

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403
Set Command Library
Comments
• About the Session Reference Day : This is a mandatory
parameter that determines the start day of data collection
through session programming. It is also used with the
Offset parameter to modify the session start and end times
for a fixed number of minutes per day.
The Session Reference Day is the three-digit day of the
year (DOY) where January 1 is day 001 and December 31
is day 365 (or day 366 in leap years).
The Session Reference Day must be equal to or less than
the current day for session programming to run. For
example, if today is day 191 and the Session Reference
Day is set to 195, the receiver will not begin activating
valid sessions for 4 days, or until the current day is equal
to the Session Reference Day.
• About the Session Offset : This optional parameter was
designed specifically for users who wish to collect data
from the identical GPS satellite window every day. The
GPS satellite window moves backwards 4 minutes per day.
The format of this parameter is in minutes and seconds
(mmss), so by setting the Session Offset to 0400, the
activated sessions will start and end 4 minutes earlier
each day.
This parameter is used with the Session Reference Day to
determine the offset from the given start time. The
receiver will multiply the difference between the current
day and the Session Reference Day, and multiply this
times the Session Offset. The session start and end times
will then be moved this amount of time backwards.
For example, assume the Session Reference Day is set to
201, the current day of the year is 204, and the Session
Offset is set to 0400 (4 minutes). The receiver will
multiply 3 (days) times 4 (minutes/day), and then subtract
12 minutes from the session start and end times. If the
"set" session start time for day 201 is 01:30, then the
actual start time on day 204 will be 01:18.
• The command will be NAKED if you attempt to change the
memory location (d4) while a session is in progress.
PE2,d18
Period of RINEX measurements, in seconds,
for the second RINEX file. A second RINEX
file will be generated only if the period is
defined as different from “0”.
0-60 0
*cc Optional checksum *00-*FF
Parameter Description Range Default