Passive Antenna Reference Design - Quectel LC79D Hardware Design

Active Antenna
C1 is used to block DC from VCC_RF. C2, C3 and R1 are reserved matching circuits for antenna
impedance modification. By default, R1 is 0Ω, C1 is 100pF, while C2 and C3 are not mounted.
The inductor L1 is used to prevent the RF signal from leaking into the VCC_RF and route the bias supply
to the active antenna. The recommended value of L1 is no less than 68nH. R2 can protect the whole circuit
in case the active antenna is short-circuited to ground.

4.2.2. Passive Antenna Reference Design

The following figure is a typical reference design for passive antenna.
Passive Antenna
LC79D_Hardware_Design
П Matching Circuit
C1 100pF
R1
0R
R2 10R
Figure 10: Reference Design for Active Antenna
П Matching Circuit
R1
0R
Figure 11: Reference Design for Passive Antenna
GNSS Module Series
LC79D Hardware Design
LC79D Module
RF_IN
VCC_RF
LC79D Module
RF_IN
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