Spectracom 8194B, Инструкция по эксплуатации

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8194B, 8195B, 8197B Spectracom Corporation
GPS Ageless Master Oscillator Instruction Manual 4-32
Example: HEX code word 08A0 translates to the following flags set:
Bit 11:
Used for Time
Bit 7: Used for Position Fix
Bit 5: Satellite Anti-Spoof Flag Set
Q = Qualified GPS: YES=Y, NO=N.
The received quality of the GPS signal is continuously monitored. The criteria used in
qualifying the GPS signal is listed below:
•
Dilution of Precision, 0
≤
DOP<10
•
Vehicle Identification Number, VID>1
•
Channel Tracking Mode, MODE=08
•
Relative Signal Strength, STREN>40
•
Position Fix Bit Set, BIT7=1
The GPS signal is qualified whenever four (4) or more satellites meet the above criteria
for one (1) minute.
4.5.7 Location
This command is to read or set the
Location
. The GPS receiver will automatically find
its correct position, but the time to first fix can be shortened by entering an approximate
position. The GPS receiver constantly calculates its position based on the satellites it is
receiving. Once the unit has acquired its first fix, entering a new position using this
command has no effect. Also, after initial installation the receiver will keep its current
position in Non-Volatile RAM so that on subsequent power cycles the unit will reach first
fix much faster than at initial installation.
wlocLDDMMSSMMMLDDDMMSSMMM
wlocLDDMMSSMMMLDDDMMSSMMM
Where L= latitude direction N or S, DD= degrees 00 to 90, MM= minutes, SS= seconds,
MMM= milliseconds, L= longitude direction E or W, DDD= degrees 000 to 180, MM=
minutes, SS= seconds, MMM= milliseconds.
rloc
rlocLDDMMSSMMMLDDDMMSSMMMHHHHHP
First 21 characters same as wloc, plus HHHHHP where HHHHH= height in meters, and
P= Y or N for position Hold yes or no.