Product Info

Smart LTE Module Series
SC20 Hardware Design
SC20_Hardware_Design Confidential / Released
6-74
/ 122
LTE-TDD Band41
2555~2655
2555~2655
MHz
The bandwidth of LTE-TDD Band 41 for SC20-J is 2545MHz~2655MHz, and the corresponding channel
range is 40140~41240.
6.1.2. Reference Design of Main and Rx-diversity Antenna Interfaces
A reference circuit design for main and Rx-diversity antenna interfaces is shown as below. A π-type
matching circuit should be reserved for better RF performance. The π-type matching components
(R1/C1/C2, R2/C3/C4) should be placed as close to the antennas as possible and are mounted according
to the actual debugging. C1, C2, C3 and C4 are not mounted and a 0Ω resistor is mounted on R1 and R2
respectively by default.
Figure 31: Reference Circuit Design for Main and Rx-diversity Antenna Interfaces
6.1.3. Reference Design of RF Layout
For user’s PCB, the characteristic impedance of all RF traces should be controlled as 50Ω. The
impedance of the RF traces is usually determined by the trace width (W), the materials’ dielectric constant,
the distance between signal layer and reference ground (H), and the clearance between RF trace and
ground (S). Microstrip line or coplanar waveguide line is typically used in RF layout for characteristic
impedance control. The following are reference designs of microstrip line or coplanar waveguide line with
different PCB structures.
NOTE