ME310G1 Hardware Design Guide
1VV0301588 Rev. 12
Page 58 of 96
2021-06-14
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Place EM noisy devices as far as possible from antenna line.
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Keep the antenna line away from power supply lines.
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Keep the antenna line away from GSM RF lines.
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If there are noisy EM devices around the PCB hosting the module, such as fast
switching ICs, take care of the shielding of the antenna line by burying it inside the
layers of the PCB and surrounding it with the Ground planes, or shielding it with a
metal frame cover.
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If you do not have noisy EM devices around the PCB hosting the module, use a
strip-line on the superficial copper layer for the antenna line. The line attenuation
will be lower than a buried one.
Hardware-based solution for GNSS and LTE coexistence
When a stand-alone GNSS receiver is present in the user application, the LTE
transmission may desensitize the GNSS receiver in particular if the decoupling between
the LTE and GNSS antennas is low. A SAW filter can be added on LTE side, to protect
GNSS receiver from LTE out-of-band emissions, as described in the diagram below.
When using the GNSS receiver embedded in the ME310G1 module, there is no condition
for degradation, since the LTE part and the GNSS part are never active simultaneously,
therefore the filtering on the LTE side is not necessary.
Figure 9: SAW filter on LTE side
