N1_Hardware_User_Guide
Copyright © Neoway Technology Co., Ltd
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7 RF Interface
7.1 2G/3G RF Design and PCB Layout
RF_ANT_TRX is the antenna pin of N1. A 50 Ω antenna is required. VSWR ranges from 1.1 to 1.5. The
antenna should be well matched to achieve best performance. It should be installed far away from high
speed logic circuits, DC/DC power, or any other strong disturbing sources.
A 50 Ω antenna is required. VSWR ranges from 1.1 to 1.5. The antenna should be well matched toachieve
the best performance.
For multiple-layer PCB, the trace between the antenna pad of module and the antenna connector, should
have a 50 Ω characteristic impedance, and be as short as possible. The trace should be surrounded by
ground copper. Place plenty of via holes to connect this ground copper to main ground plane, at the copper
edge.
If the trace between the module and connector has to be longer, or built-in antenna is used, a π-type
matching circuit is needed, as shown in Figure 7-1.
Figure 7-1
Reference of antenna matching design
Big RF solder pad can result in great parasitic capacitance, which will affect the antenna performance.
Remove the copper on the first and second layers under the RF solder pad.
Figure 7-2
Recommended RF PCB design
If users adopt RF antenna connections, the GSC RF connector MM9329-2700RA1 from Murata is
recommended. Figure 7-3 shows the encapsulation specifications.
