SARA-G3 and SARA-U2 series - System Integration Manual
UBX-13000995 - R26
System description
Page 81 of 217
1.13
System features
1.13.1
Network indication
Not supported by SARA-G300 and SARA-G310 modules.
The
GPIO1
, or the
GPIO2
,
GPIO3
,
GPIO4
and, on SARA-U2 series only, the
SIM_DET
, alternatively from their
default settings, can be configured to indicate network status (i.e. no service, registered home network,
registered visitor network, voice or data call enabled), by means of the AT+UGPIOC command.
For the detailed description, see section 1.11 and the
u-blox AT Commands Manual
[3], GPIO commands.
1.13.2
Antenna detection
Not supported by SARA-G300 and SARA-G310 modules.
ANT_DET
pin of SARA-G340, SARA-G350 and SARA-U2 series modules is an Analog to Digital Converter (ADC)
provided to sense the presence of an external antenna when optionally set by the +UANTR AT command.
The external antenna assembly must be provided with a built-in resistor (diagnostic circuit) to be detected, and
an antenna detection circuit must be implemented on the application board properly connecting the antenna
detection input (
ANT_DET
) to the antenna RF interface (
ANT
).
For more details regarding feature description and detection / diagnostic circuit design-in, see sections 1.7.2 and
2.4.2 and the
u-blox AT Commands Manual
1.13.3
Jamming detection
Not supported by SARA-G300 and SARA-G310 modules.
In real network situations, modules can experience various kind of out-of-coverage conditions: limited service
conditions when roaming to networks not supporting the specific SIM, limited service in cells which are not
suitable or barred due to operators’ choices, no cell condition when moving to poorly served or highly interfered
areas. In the latter case, interference can be artificially injected in the environment by a noise generator covering
a given spectrum, thus obscuring the operator’s carriers entitled to give access to the cellular service.
The Jamming Detection Feature detects such “artificial” interference and reports the start and stop of such
conditions to the client, which can react appropriately by e.g. switching off the radio transceiver to reduce
power consumption and monitoring the environment at constant periods.
The feature detects, at the radio resource level, an anomalous source of interference and signals it to the client
with an unsolicited indication when the detection is entered or released. The jamming condition occurs when:
The module has lost synchronization with the serving cell and cannot select any other cell
The band scan reveals at least n carriers with power level equal or higher than the threshold
On all such carriers, no synchronization is possible
The client can configure the number of minimum disturbing carriers and the power level threshold by using the
AT+UCD command [3].
The jamming condition is cleared when any of the above mentioned statements does not hold.
The congestion (i.e. jamming) detection feature can be enabled and configured by the +UCD AT command, and
the jamming condition can be additionally notified by GPIO pins of SARA-G3 modules product versions “02”
onwards (for more details, see the
u-blox AT Commands Manual
[3], +UCD and +UGPIOC AT commands).
