Hardware Guide
Table Of Contents
- Fibocom_FM101-CG_Hardware_Guide_V1.0.pdf
- FM101-CG-20: Hardware Guide
- Contents
- Change History
- 1. Foreword
- 2. Product Overview
- 3. Pin Definition
- 4. Electrical Characteristics
- 5. Functional Interface
- 6. Radio Frequency
- 6.1. RF Interface
- 6.2. Operating Bands
- 6.3. Transmitting Power
- 6.4. Receiving Sensitivity
- 6.5. GNSS Receiving Performance
- 6.6. Antenna Design
- 6.7. PCB Routing Design
- 6.8. Main Antenna Design
- 6.9. Diversity and MIMO Antenna Design
- 6.10. GNSS Antenna Design
- 6.11. Other Interfaces
- 7. Thermal Design
- 8. Electrostatic Protection
- 9. Structural Specifications
- Appendix A: Acronyms and Abbreviations
- Module FCC & ISED警语 for Fibocom
performance is closely related to this cabling. PCB parameters that will affect the cabling
impedance include:
•
Trace width and thickness
•
Dielectric constant and thickness of media
•
Thickness of pad
•
Distance from ground line
•
Nearby traces
6.7.2. Impedance Design
The RF impedance of the two antennas’ interface should to be controlled within 50Ω.
In practical application, RF routing mode is designed according to other parameters of
PCB, such as reference layer thickness, number of layers and stacking. Different
reference GND layer will lead to different routing design.
6.7.3. 3W Principle
During antenna RF signal cabling design on PCB, the first thing you need to consider is to
follow "3W principle".
In order to reduce crosstalk between the lines, please ensure that line spacing is large
enough. If the line spacing is at least 3 times of the line width, 70% of the electric field
between the lines will not interfere with each other, and this is called "3W principle".
Figure 21. 3W principle
6.7.4. Impedance Design for Four-layer Board
The thickness of four-layer board is 1.0 mm. RF line is routed on Lay 1, and reference
6. Radio Frequency
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