44
Measurements Used
•
This radio button group shows what code measurements will be used to compute the
receiver’s standalone position. The corresponding receiver parameter is
/par/pos/sp/meas
.
For a single-frequency receiver, the radio buttons
P/L1
,
P/L2
and
Iono-
Free
will be gray.
If the checkbox
Iono-Correction
is selected, the receiver will correct the pseudoranges for
ionosphere (based on the model defined in ICD-GPS-200, Revision C) before using them in position
computation. The corresponding receiver parameter is
/par/pos/sp/iono
. Note that if both
Iono-
Free
and
Iono-Correction
are selected, the first overrides the second.
If the checkbox
Tropo-Correction
is selected, the pseudoranges will be corrected for tropo-
sphere before being used in position computation. The corresponding receiver parameter is
/par/pos/sp/tropo
.
Note that the above mentioned receiver parameters,
/par/pos/sp/meas,
/par/pos/sp/iono
and
/par/pos/sp/tropo
, apply only to
absolute
position computa-
tion.
Satellite management
Satellites tracked
•
The checkboxes
GPS
and
GLONASS
are used to allow tracking of GPS and GLON-
ASS satellites, respectively. The
GPS
checkbox is associated with the receiver parame-
ter
/par/lock/gps/sat
. The
GLONASS
checkbox relates to
/par/lock/glo/fcn
.
Satellites used in pos.
•
Use the checkboxes
GPS
and
GLONASS
to specify what satellite systems (only GPS,
only GLONASS, or both) will be used in position computation. The
GPS
checkbox is as-
sociated with the receiver parameter
/par/pos/gps/sat
. The
GLONASS
checkbox corre-
sponds to
/par/pos/glo/sat
.
GPS | GLONASS | WAAS
Use these tabs to explicitly specify which of the GPS, GLONASS and WAAS satellites are enabled for
tracking and position computation.
The first tab, as its name implies, deals with the GPS satellites (Figure 30).