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FIBOCOM SC138-
NA
Series Hardware Guide
72/88
Figure 4-3 Coplanar waveguide structure of four-layer PCB (reference ground layer 3)
Figure 4-4 Coplanar waveguide structure of four-layer PCB (reference ground layer 4)
In the circuit design of RF antenna interface, in order to ensure the good performance and ALT of RF
signal, the following design principles are recommended in the circuit design:
The impedance simulation calculation tools shall be used to accurately control the 50 Ω impedance
of the RF signal line.
GND pins adjacent to RF pins shall not be hot bonding pads and shall be fully contacted with the
ground.
The distance between RF pin and RF connector shall be as short as possible; in order to avoid right-
angle routing, the recommended routing angle is 135°.
When connecting the device package, it shall be noted that the signal pin shall be kept at a certain
distance from the ground.