User's Manual

Table Of Contents
SIM7090G User Manual V1.01
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4.2 LTE Antenna Design Guide
Users should connect antennas to SIM7090G’s antenna pads through micro-strip line or other types of RF
trace and the trace impedance must be controlled in 50Ω. SIMCom recommends that the total insertion loss
between the antenna pads and antennas should meet the following requirements:
Table 32: 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 25: Antenna matching circuit (MAIN_ANT)
In above figure, the components R1, C1, C2 and R2 are used for antenna matching, the values 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 SIM7090G and antenna must be controlled in
50Ω.
Two TVS are recommended in the table below.