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Figure 33: Reference Circuit Design for GNSS Active Antenna
It is recommended to use a passive GNSS antenna when LTE B13 or B14 is supported, as the use of active
antenna may generate harmonics which will affect the GNSS performance.
6.4. RF Routing Guidelines
F
or 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 34: Microstrip Design on a 2-layer PCB
NOTE
