Installation Instructions

LISA-U2 series - System Integration Manual
UBX-13001118 - R19 Early Production Information Features description
Page 140 of 175
3 Features description
3.1 Network indication
The GPIO1, GPIO2, GPIO3, GPIO4 or GPIO5 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 1.12 and to u-blox AT Commands Manual [2], GPIO commands.
3.2 Antenna detection
Antenna presence detection capability is provided, evaluating the resistance from the ANT pin to GND by means
of an internal antenna detection circuit. The external antenna assembly must be provided with a built-in resistor
(diagnostic circuit) to be detected.
The antenna detection feature can be enabled through the +UANTR AT command.
For more details regarding feature description and diagnostic circuit design-in see the section 2.4.4, and the
u-blox AT Commands Manual [2].
3.3 Jamming Detection
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 GSM/UMTS 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 in order to
reduce power consumption and monitoring the environment at constant periods.
The feature consists of detecting, at radio resource level, an anomalous source of interference and signaling 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 threshold
 On all such carriers, no synchronization is possible
The number of minimum disturbing carriers and the power level threshold can be configured by the client by
using the AT+UCD command [2].
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 (for
more details see the u-blox AT Commands Manual [2]).