Viavi 87339, Руководство по эксплуатации

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Testing
4 -6
4.1.4 Setup Basic Trajectory Simulation
Perform the following steps for Setup:
STEP PROCEDURE
1. Press Power On/Off Key for a minimum of one second to power up test set.
2. Select Launch Bar tab to display launch bar.
3. Select Setup function key to display Setup Window.
4. Select Simulation tab.
5. Confirm the following settings and change as necessary:
GNSS:
GNSS = GPS
Carrier = L1
SBAS = Off
Simulation = Trajectory
Digital Noise = OFF – when coupling to the receiver antenna. ON – when
connecting directly to the receiver, bypassing the antenna/LNA.
NOTE:
Use of digital noise via receiver antenna will result in degraded SV Signal to
Noise ratio and may cause receiver to loose track or not obtain a stable fix.
Fading = None
PRN Signal = Fixed
Position Source = User
Simulation Start Time:
Clock = User
Date = For optional entry of date
Time = For optional entry of time
RF Output:
RF Level = When setting the output level of GPS generated signal, a setting of
- 115 to - 120 dB should be adequate for most receivers. When directly connecting
to a receiver, the nominal gain of the antenna should be taken into consideration
and the output level of the GPSG-1000 adjusted accordingly.
RF Port = COUPLER (if using antenna coupler) or DIRECT (direct connect to GPS
UUT)
Units = Imperial
6. Select Almanac tab on the File page and press Load Default.
7. Select I/O tab.
Loss:
Coupler Loss = Figure in dB marked on Antenna Coupler
Coupler Cable = Figure in dB marked on RF Coax Cable
Direct Cable = Figure in dB marked on RF Coax Cable
Input/Output:
Ext Ref Out = OFF
Reference Source = INT
Trigger = Auto
8. Select GPS RX function key from the Launch Bar.
9. Ensure that the GPS receiver antenna is correctly connected to the GPSG-1000
and that the test set has an unobstructed view of the sky.
10. To start the recording process press Record Trajectory button.