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FIBOCOM SQ806-W Series Hardware Guide
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Figure 5-3 Four-layer PCB coplanar waveguide structure (reference ground layer 3)
Figure 5-4 Four-layer PCB coplanar waveguide structure (reference ground layer 4)
In the design of RF antenna interface circuit, in order to ensure good performance and reliability of the RF
signal, it is recommended to observe the following design principles:
The impedance simulation tool should be used to accurately control the RF signal cable at 50Ω
impedance.
The GND pin adjacent to the RF pin should not have thermal welding plate and should be in full
contact with the ground.
The distance between the RF pin and the RF connector should be as short as possible. At the same
time, avoid the right-angle route. The recommended route angle is 135 degrees.
Attention should be paid to the encapsulation of the component package and the signal pin should
be kept at a certain distance from the ground.
The reference ground plane of the RF signal cable should be kept intact; adding a certain amount of
ground holes around the signal and the reference ground can improve the RF performance; the
