CLM920_RC3(RV3 RE3)LCC Series CAT1 Module Hardware Manual
Shanghai YUGE Information Technology Co., Ltd.
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The antenna is a sensitive device, which is easily affected by the external surrounding
environment, so it needs to be far away from the digital clock line, DC power and other
interference signals. It is recommended to use a complete ground plane as the reference
ground.
The LAYOUT trace of the antenna should be as short as possible, go straight as far as
possible, avoid via holes and layer turning, three-dimensionally cover the ground, and
add more ground holes on both sides of the trace for isolation.
GNSS antennas can use passive ceramic antennas or other types of GPS antennas, LNA is
integrated inside the module, no need to add LNA circuit outside.
3.15.2 RF trace reference
The main set of the CLM920_RC3 module and the GNSS antenna are led out by pads.
The antenna pad to the antenna feed point must use microstrip lines or other types of RF
traces. The characteristic impedance of the signal line should be controlled at 50
Ω
.
The impedance of the RF signal line is determined by the dielectric constant of the
material, the width of the trace (W), the ground clearance (S), and the height of the reference
ground plane (H). Therefore, RF traces need to use impedance simulation tools to calculate
the impedance value of RF traces.
Figure 3-26 The complete structure of the microstrip line
