Symmetricom XL-GPS, Руководство пользователя

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F60 – GPS Receiver Satellite List
F60 – GPS Receiver Satellite List
Use function F60 to display the identification number and signal strength of tracked or
current satellites. ‘Tracked’ means a satellite’s signal is being received and interpreted by the
receiver (or that the XL-GPS has GPS data that suggests this satellite should be visible to
the antenna).
GPS satellite are grouped into the following categories:
• Tracked: the XL-GPS is receiving the GPS signal, but isn’t using it to calculate time
and position.
• Current: the XL-GPS is using the satellite’s GPS signal to calculate time and position.
• Bad: the GPS satellite is transmitting information that it has been removed from
service.
• Rejected: the XL-GPS Receiver’s TRAIM feature has detected anomalous signals
from this satellite and has quarantined it from the timing solution for 12 hours.
GPS satellite signal strengths are reported in units of dBW. Signals below -170 dBW (e.g., -
171 dBW) are not usable by the GPS receiver.
See “GPS Signal Strength Requirements” on
page 23.
If you’re using the keypad interface, use the UP/DOWN ARROWs to scroll through the list of
satellites.
Command Line
Use Serial Function F60 to request a list of all, current, and tracked satellites. To display the
list, enter a string using the following format:
F60<S><TYPE><CR>
XL-GPS responds with approximately 32 lines that use the following format:
F60<S>prn<NN><S><STATE> tracked current<LEVEL><CR><LF>
where:
F60
= ASCII string indicating function F60.
<S> = ASCII space character one or more.
<SEP>
= One or more separator characters; either space, comma or tab.
<TYPE>
= ALL, CURRENT, TRACKED, BAD, or REJECTED.
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