Reference Design Of Rf Routing - Quectel FC908A Hardware Design

Wi-Fi&Bluetooth Module Series
Figure 10: Reference Design

3.8.4. Reference Design of RF Routing

For user's PCB, the characteristic impedance of all RF traces shall 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 11: Microstrip Design on a 2-layer PCB
Figure 12: Coplanar Waveguide Design on a 2-layer PCB
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