Spectracom GSG-5 series, Руководство пользователя с руководством по SCPI

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BEIDOU
China; regional system (Asia); planned global expansion; open system
QZSS
Japan; regional system
IRNSS
India; regional system
3.5.10.2 Number of Satellites
The maximum number of satellites to be simulated by GSG in a given scenario is specified sep
arately for each available GNSS system. (For SBAS, see "SBAS Satellites" on page 77).
To edit the number of satellites for a GNSS system, navigate to: Select > [ Select Scenario ] >
Configure Scenario : View 3/3 > [ Satellite System ]: Enter a number "Number of Satellites"
above
The theoretical maximum number of satellites that can be simulated is 64, but this number also
depends on:
The license and GSG model used (number of available channels )
How many frequency bands are used, e.g., if 64 channels are available, 64 GNSS L1
satellite signals can be simulated, or, e.g., 32 L1/L2 satellite signals. (Note that GPS L2
and L2C are using separate channels, as are the Galileo bands E5a and E5b.)
The default setting is
Auto
, i.e. GSG will determine the number of satellites simulated at any
given time during scenario execution.
Note: If GSG runs out of free channels when in Auto mode, not all satellites will be
simulated.
3.5.10.3 Frequency Bands and Signal De-/Activation
When testing GNSS receivers, it is oftentimes required to test for multi-frequency, multi-con
stellation performance. All of the four major GNSS systems, i.e. GPS, Glonass, Galileo, and
BeiDou, transmit numerous signals across several frequencies, but through international cooper
ation, these frequency bands have been coordinated:
The RF signals transmitted from satellites of different constellation systems…
… are transmitted on frequencies close to each other, yet they do not interfere with each
other
… can be decoded by one receiver (if supported by the receiver manufacturer)
… can be grouped into four main bands.
These four frequency bands are:
3.5 "Select" Menu
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User Manual GSG-5/6 Series Rev. 26
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