LPWA Module Series
BG96 Hardware Design
BG96_Hardware_Design 51 / 79
5.1.4. Reference Design of RF Layout
For user
’s PCB, the characteristic impedance of all RF traces should be controlled to 50Ω. The
impedance of the RF traces is usually determined by the trace width (W), the materials
’ dielectric constant,
height
from the reference ground to the signal layer (H),
and the clearance 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 23: Microstrip Design on a 2-layer PCB
Figure 24: Coplanar Waveguide Design on a 2-layer PCB
Figure 25: Coplanar Waveguide Design on a 4-layer PCB (Layer 3 as Reference Ground)
