User Manual

Table Of Contents
SARA-R4 series-AT commands manual
UBX-17003787 - R16
23Positioning
Page 270 of 401
autonomously generate an accurate satellite orbit representation («AssistNow Autonomous data») that is
usable for navigation much longer than the underlying broadcast ephemeris was intended for.
Local Aiding feature provides a functionality so that u-blox receivers is instructed to dump the current state
of their internal navigation database to the cellular module file system. This information is sent back to the
receiver (e.g. after a period when the receiver was turned off) restoring the database to its former state, and
thus allows the receiver to restart rapidly. Local aiding feature does not need for a access to the Internet.
The +UGPS AT command allows the activation/deactivation of AssistNow Online, Offline, Autonomous and
Local Aiding features.
The AssistNow Offline and AssistNow Autonomous features are exclusive and should not be used at the
same time. Every satellite will be ignored by AssistNow Autonomous if there is AssistNow Offline data
available for it.
Table 24 summarizes the GNSS AT commands related with AssistNow services:
AT command AssistNow Online AssistNow Offline AssistNow Autonomous Local Aiding
+UGPS Enable/disable the feature Enable/disable the feature Enable/disable the feature Enable/disable the feature
+UGAOP Configure UDP for A-GPS
(deprecated)
+UGAOF Configure HTTP for A-
GPS (deprecated)
+UGSRV Configure HTTP for A-
GNSS
Configure Auth Token for
A-GNSS
Configure HTTP for A-
GNSS
Configure Auth Token for
A-GNSS
+UGAOS Force AssistNow Online
data download request
Force AssistNow Offline
data download request
Force AssistNow
Autonomous operation
Download/Upload of local
aiding data from/to GNSS
receiver to cellular module
Table 24: AssistNow services Overview
23.3GNSS
23.3.1GNSS power management +UGPS
+UGPS
SARA-R410M-02B SARA-R410M-52B SARA-R410M-63B SARA-R410M-73B SARA-R410M-83B
SARA-R412M
Modules
SARA-N4
Syntax PIN required Settings saved Can be aborted Response time Error referenceAttributes
full No No No < 10 s +CME Error
23.3.1.1Description
Switches on or off a u-blox GNSS receiver connected to the cellular module via a dedicated DDC (I
2
C)
interface. For more details about the connection between cellular module and u-blox GNSS receiver, see the
corresponding module system integration manual.
Furthermore the command sets the aiding type to be used to enhance GNSS performance, e.g. decreasing
Time To First Fix (TTFF). The supported aiding types are: Local aiding, AssistNow Online, AssistNow Offline,
AssistNow Autonomous.
For a more detailed description on aiding modes and possible suggestions, please see AssistNow services.
The AssistNow Autonomous feature may be not fully supported on all Multi-GNSS receivers. For more
details on AssistNow Autonomous feature see the corresponding u-blox-GNSS receiver description.
It is possible to combine different aiding modes: to enable them the sum of the <mode> value of the interested
aiding modes is needed (e.g.: aiding <aid_mode>=3 means local aiding plus AssistNow Offline). Moreover it is
also possible to switch from one aiding mode to another one without powering off the GNSS receiver. If the
following sequence is provided (AT+UGPS=1,1 and then AT+UGPS=1,5) at the beginning the GNSS receiver will
power on with local aiding support and after the second command will be added the AssistNow Online. After
the second command the local aiding is not restarted, therefore the +UUGIND URC for it will not be sent again.