Smart LTE Module Series
SC66 Hardware Design
SC66_Hardware_Design 99 / 139
1.
1)
The bandwidth of LTE-TDD B41 for SC66-CE* and SC66-J* is 120MHz (2535MHz~2655MHz), and
the corresponding channel ranges from 40040 to 41240.
2.
2)
The bandwidth of LTE-TDD B41 for SC66-A and SC66-E is 200MHz (2496MHZ~2690MHz), and
the corresponding channel ranges from 39650 to 41589.
3. “*” means under development.
6.1.1. Main and Rx-diversity Antenna Interfaces Reference Design
A reference circuit design for main and Rx-diversity antenna
interfaces is shown below. A π-type
matching circuit for
each antenna should be reserved for better RF performance, and the π-type matching
components (R1/C1/C2, R2/C3/C4) should be placed as close to the antennas as possible. The
capacitors are not mounted by default and resistors are 0
Ω.
ANT_MAIN
R1 0R
C1
Module
Main
antenna
NM
C2
NM
R2 0R
C3
Diversity
antenna
NM
C4
NM
ANT_DRX
Figure 36: Reference Circuit Design for Main and Rx-diversity Antenna Interfaces
6.1.2. Reference Design of RF Layout
For user’s PCB, the characteristic impedance of all
RF traces should be controlled to 50Ω. The
impedance of the RF traces is usually determined by the trace width (W), the materials’ dielectric constant,
height from the reference ground to the signal layer (H), and the clearance between RF traces and
grounds (S). Microstrip or coplanar waveguide is typically used in RF layout to control characteristic
NOTES