u-blox SARA-G3 Series System Integration Manual Download

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SARA-G3 series - System Integration Manual

UBX-13000995 - R06

Objective Specification

System description

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via a dedicated DDC (I

C) interface. A 2

interface connected to the positioning receiver is not

necessary: AT commands via the UART serial interface of the wireless module allows a fully control of the
GNSS receiver from any host processor.
SARA-G350 modules feature embedded GPS aiding that is a set of specific features developed by u-blox
to enhance GNSS performance, decreasing Time To First Fix (TTFF), thus allowing to calculate the
position in a shorter time with higher accuracy.

SARA-G350 modules support these GPS aiding types:



Local aiding



AssistNow Online



AssistNow Offline



AssistNow Autonomous

The embedded GPS aiding features can be used only if the DDC (I

C) interface of the wireless module

is connected to the u-blox GNSS receivers.

SARA-G350 wireless modules provide additional custom functions over GPIO pins to improve the
integration with u-blox positioning chips and modules. GPIO pins can handle:



GNSS receiver power-on/off: “GNSS supply enable” function provided by

GPIO2

improves the

positioning receiver power consumption. When the GNSS functionality is not required, the positioning
receiver can be completely switched off by the wireless module that is controlled by the application
processor with AT commands



The wake up from idle-mode when the GNSS receiver is ready to send data: “GNSS data ready”
function provided by

GPIO3

improves the wireless module power consumption. When power saving is

enabled in the wireless module by the AT+UPSV command and the GNSS receiver does not send
data by the DDC (I

C) interface, the module automatically enters idle-mode whenever possible. With

the “GNSS data ready” function the GNSS receiver can indicate to the wireless module that it is
ready to send data by the DDC (I

C) interface: the positioning receiver can wake up the wireless

module if it is in idle-mode, so the wireless module does not lose the data sent by the GNSS
receiver even if power saving is enabled



The RTC synchronization signal to the GNSS receiver: “GNSS RTC sharing” function provided by

GPIO4

improves GNSS receiver performance, decreasing the Time To First Fix (TTFF), and thus

allowing to calculate the position in a shorter time with higher accuracy. When GPS local aiding is
enabled, the wireless module automatically uploads data such as position, time, ephemeris, almanac,
health and ionospheric parameter from the positioning receiver into its local memory, and restores this
to the GNSS receiver at the next power up of the positioning receiver

For more details regarding the handling of the DDC (I

C) interface, the GPS aiding features and

the GNSS related functions over GPIOs, refer to section 1.11, to the

u-blox AT Commands Manual

[2] (AT+UGPS, AT+UGPRF, AT+UGPIOC AT commands) and the

GNSS Implementation

Application Note [21].

“GNSS data ready” and “GNSS RTC sharing” functions are not supported by all u-blox GNSS
receivers HW or ROM/FW versions. Refer to the

GNSS Implementation Application Note [21] or to

the

Hardware Integration Manual of the u-blox GNSS receivers for the supported features.