NB-IoT Module Series
BC66 Hardware Design
BC66_Hardware_Design 34 / 50
4.1.2. Antenna Requirements
To minimize the loss on RF trace and RF cable, please pay attention to the antenna design. The following
tables show the requirements on NB-IoT antenna.
Table 14: Antenna Cable Insertion Loss Requirements
Band
Requirements
LTE B5/B8/B12*/B13*/B17*/
B18*/B19*/B20/B26*/B28*
Cable Insertion loss <1dB
LTE B1/B2*/B3/B25*/B66*
Cable Insertion loss <1.5dB
“*” means under development.
Table 15: Required Antenna Parameters
Parameters
Requirements
Frequency Range
Depend on the frequency band(s) provided by the network operator
VSWR
≤2
Gain (dBi)
1
Max Input Power (W)
50
Input Impedance (Ω)
50
Polarization Type
Vertical
4.1.3. Reference Design of RF Layout
For user’s PCB, the characteristic impedance of all RF traces should be controlled as 50
Ω
. 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