SARA-R4 series - System Integration Manual
UBX-16029218 - R06
Product testing
Page 90 of 102
This feature allows the measurement of the transmitter and receiver power levels to check component assembly
related to the module antenna interface and to check other device interfaces from which depends the RF
performance.
To avoid module damage during transmitter test, a proper antenna according to module
specifications or a 50
termination must be connected to the ANT port.
To avoid module damage during receiver test, the maximum power level received at the ANT
port must meet module specifications.
The AT+UTEST command sets the module to emit RF power ignoring LTE signaling protocol. This emission
can generate interference that can be prohibited by law in some countries. The use of this feature is
intended for testing purpose in controlled environments by qualified user and must not be used during
the normal module operation. Follow instructions suggested in u-blox documentation. u-blox assumes no
responsibilities for the inappropriate use of this feature.
Figure 45 illustrates a typical test setup for such RF functional test.
Application Board
SARA-R4 series
ANT
Application
Processor
AT
commands
Cellular
antenna
Spectrum
Analyzer
or
Power
Meter
IN
Wideband
antenna
TX
Application Board
SARA-R4 series
Application
Processor
AT
commands
Signal
Generator
OUT
Wideband
antenna
RX
ANT
Cellular
antenna
Figure 45: Setup with spectrum analyzer or power meter and signal generator for radiated measurements