GSM/GPRS/NB-IoT Module Series
BC68&M66 Compatible Design
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4.9. RF Antenna Interface
RF_ANT and BT_ANT of M66 are compatible to RF_ANT of BC68. The RF antenna interface has an
impedance of 50Ω. A reference circuit for the interface is shown below. In order to achieve better RF
performance, a π-type matching circuit should be reserved, and the π-type matching components
(R1/C1/C2) should be placed as close the antenna as possible. By default, the resistance of R1 is 0Ω and
capacitors C1 and C2 are not mounted.