RCB-F9T - Integration manual
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Save-on-Shutdown:
The receiver can be instructed to dump its current state to flash memory
as part of the shutdown procedure; this data is then automatically retrieved when the receiver
is restarted. For more information, see the description of the UBX-UPD-SOS messages in the
RCB-F9T Interface description [
].
3.6.4 AssistNow Online
AssistNow Online is u-blox's end-to-end Assisted GNSS (A-GNSS) solution for receivers that have
access to the internet. Data supplied by the AssistNow Online Service can be directly uploaded to
a u-blox receiver in order to substantially reduce time to first fix (TTFF), even under poor signal
conditions (typically around 2 seconds; see RCB-F9T Data sheet [
] "Aided start"). The system
works by collecting data such as ephemeris and almanac from the satellites through u-blox's "Global
Reference Network" of receivers and providing this data to customers in a convenient form that can
be forwarded directly to u-blox receivers.
The AssistNow Online Service uses a simple, stateless, HTTP interface. Therefore, it works on all
standard mobile communication networks that support internet access, including GPRS, UMTS and
Wireless LAN. No special arrangements need to be made with mobile network operators to enable
AssistNow Online.
Figure 7: MGA architecture
The data returned by the AssistNow Online Service is a sequence of UBX-MGA messages, starting
with an estimate of the current time in the form of a UBX-MGA-INI-TIME_UTC message.
AssistNow Online currently supports GPS, GLONASS, BeiDou, Galileo, and QZSS.
Customers may choose to use third party sources of assistance data instead of using
the AssistNow Online Service. Customers choosing this option will need to ensure that
the data is converted from the format used by the third party source to the appropriate
MGA messages. However, it is important to ensure that the receiver has an estimate of the
current time before it processes any other assistance data. For this reason, it is strongly
recommended to send a UBX-MGA-INITIME_UTC or UBX-MGA-INI-TIME_GNSS as the first
message of any assistance.
UBX-19003747 - R04
3 Receiver functionality
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Early production information