User's Manual

Smart Machine Smart Decision
SIM7500A_User Manual_V1.022016-09-29
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4.2 WCDMA/LTE Antenna Design Guide
Users should connect antennas to Module’s antenna pads through the micro-strip line or other types
of RF trace. The trace impedance must be controlled in 50Ω. SIMCom recommends that the total
insertion loss between Module and antenna should meet the following requirements:
Table 25: Trace Loss
Frequency
Loss
700MHz-960MHz
<0.5dB
1710MHz-2170MHz
<0.9dB
2300MHz-2650MHz
<1.2dB
To facilitate the antenna tuning and certification test, a RF connector and an antenna matching
circuit should be added. The following figure is the recommended circuit.
Figure 27: Antenna matching circuit (MAIN_ANT)
In above figure, the components R1,C1,C2 and R2 are used for antenna matching, the value of
components can only be achieved after the antenna tuning and usually provided by antenna vendor.
By default, the R1, R2 are 0Ω resistors, and the C1, C2 are reserved for tuning. The component D1
is a TVS for ESD protection, and it is optional for users according to application environment.
The RF test connector is used for the conducted RF performance test, and should be placed as close
as to the module’s MAIN_ANT pin. The traces impedance between Module and antenna must be
controlled in 50Ω.