Integration Manual

SARA-R4/N4 series - System Integration Manual
UBX-16029218 - R11 System description Page 36 of 157
Item
Requirements
Remarks
Maximum Gain
According to radiation exposure
limits
The power gain of an antenna is the radiation efficiency multiplied by
the directivity: the gain describes how much power is transmitted in the
direction of peak radiation to that of an isotropic source.
The maximum gain of the antenna connected to ANT port must not
exceed the herein stated value to comply with regulatory agencies
radiation exposure limits. For additional info see sections 4.2.2.
Input Power
> 24 dBm ( > 0.25 W ) for R404M /
R410M / N410
> 33 dBm ( > 2.0 W ) for R412M
The antenna connected to the ANT port must support with adequate
margin the maximum power transmitted by the modules.
Table 7: Summary of Tx/Rx antenna RF interface requirements
1.7.2 Antenna detection interface (ANT_DET)
The antenna detection is based on ADC measurement. The ANT_DET pin is an Analog to Digital Converter
(ADC) provided to sense the antenna presence.
The antenna detection function provided by ANT_DET pin is an optional feature that can be implemented
if the application requires it. The antenna detection is forced by the +UANTR AT command. See the SARA-
R4/N4 series AT Commands Manual [2] for more details on this feature.
The ANT_DET pin generates a DC current (for detailed characteristics see the SARA-R4/N4 series Data
Sheet [1]) and measures the resulting DC voltage, thus determining the resistance from the antenna
connector provided on the application board to GND. So, the requirements to achieve antenna detection
functionality are the following:
 an RF antenna assembly with a built-in resistor (diagnostic circuit) must be used
 an antenna detection circuit must be implemented on the application board
See section 2.4.2 for antenna detection circuit on application board and diagnostic circuit on antenna
assembly design-in guidelines.
1.8 SIM interface
1.8.1 SIM interface
SARA-R4/N4 series modules provide high-speed SIM/ME interface including automatic detection and
configuration of the voltage required by the connected SIM card or chip.
Both 1.8 V and 3 V SIM types are supported. Activation and deactivation with automatic voltage switch
from 1.8 V to 3 V are implemented, according to ISO-IEC 7816-3 specifications. The VSIM supply output
provides internal short circuit protection to limit start-up current and protect the SIM to short circuits.