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

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As a user you interact with the GSG by inputting the RLM parameters as a SCPI command into
the computer; GSG will then take this message and simulate its transmission on the E1 frequency
from the satellite to the distress beacon.
For more information on SCPI command syntax, and examples, see "SOURce:SCENario:RLM"
on page 286.
5.8.1 SAR Data
Each Return Link Message encapsulated in an SAR data page contains the following data:
Beacon ID (60 bits): This field is used by the beacon to discern whether the RLM received
is, indeed, addressed to itself or to some other beacon.
Message code (4 bits): Defines the message type.
Parameters field (16 bits for the short RLM, 96 bits for the long RLM). This field provides
the information that SAR operators wish to send to the Galileo-equipped beacon.
Short RLMs are used to provide the activated Galileo-equipped beacon with a short acknow
ledgement of various kinds of commands (e.g., to reduce its transmission rate).
Long RLMs are intended for more complex commands in which several parameters may be
required (e.g., to contain operational information or the coordinates of a location).
For more information on SCPI command syntax and examples, see "SOURce:SCENario:RLM"
on page 286.
5.8.2 Requirements
In order for the RLM simulation to work with GSG, the following pre-requisites must be met:
The Galileo-Option OPT-GAL must be present
GSG-5 or -6, with 8 channels (or 16 channels if GPS + GAL is required)
Firmware version 6.6.1 or greater
StudioView software Version 4.6.1.3 or greater
5.8.3 Simulating RLMs
The following is a brief outline how to setup a basic test system:
1.
Using a GSG unit, and a GNSS receiver, start a scenario that is configured with GAL
signals e.g.,
GPSGALStatic .
2.
Open StudioView on a Personal Computer (PC).
3.
Open the Console tool (Tools > Console).
4.
Connect the PC to the GSG unit by clicking the small GLOBE with PLUG icon on the left
(or click Refresh if a connection has been established before).
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User Manual GSG-5/6 Series Rev. 26
5.8 RLS (Return Link Service)