Product Info

Automotive Module Series
AG521R-NA QuecOpen Hardware Design
AG521R-NA_QuecOpen_Hardware_Design 68 / 104
ANT_MAIN
R1 0R
C1
Module
Main
Antenna
NM
C2
NM
R2 0R
C3
Diversity
Antenna
NM
C4
NM
ANT_DIV
Figure 31: Reference Circuit of RF Antenna Interfaces
ANT_DIV function is enabled by default. AT+QCFG="diversity",0 command can be used to disable receive
diversity. See document [3] for details of the command.
4.1.4. Reference Design of RF Layout
For user’s PCB, the characteristic impedance of all RF traces should be controlled to 50 Ω. The impedance of the
RF traces is usually determined by the trace width (W), the materials’ dielectric constant, the height from the
reference ground to the signal layer (H), and the spacing between RF traces and grounds (S). Microstrip or coplanar
waveguide is typically used in RF layout to control characteristic impedance. The following are reference designs
of microstrip or coplanar waveguide with different PCB structures.
Figure 32: Microstrip Design on a 2-layer PCB
NOTES