Users Manual

ME910C1 HW User Guide
1VV0301351 Rev.13 Page 74 of 106 2020-06-30
6.4.1. PCB Design guidelines
When using the ME910C1, since there's no antenna connector on the module, the
antenna must be connected to the ME910C1 antenna pad (K1) by means of a
transmission line implemented on the PCB.
This transmission line shall fulfil the following requirements:
Item Value
Characteristic
Impedance
50 ohm (+-10%)
Max Attenuation 0,3 dB
Coupling Coupling with other signals shall be avoided
Ground Plane
Cold End (Ground Plane) of antenna shall be equipotential to
the ME910C1 ground pins
The transmission line should be designed according to the following guidelines:
• Make sure that the transmission line’s characteristic impedance is 50ohm ;
• Keep line on the PCB as short as possible, since the antenna line loss shall be less than about 0,3 dB;
• Line geometry should have uniform characteristics, constant cross section, avoid meanders and abrupt
curves;
• Any kind of suitable geometry / structure (Microstrip, Stripline, Coplanar, Grounded Coplanar
Waveguide...) can be used for implementing the printed transmission line afferent the antenna;
• If a Ground plane is required in line geometry, that plane has to be continuous and sufficiently
extended, so the geometry can be as similar as possible to the related canonical model;
• Keep, if possible, at least one layer of the PCB used only for the Ground plane; If possible, use this
layer as reference Ground plane for the transmission line;
• It is wise to surround (on both sides) the PCB transmission line with Ground, avoid having other signal
tracks facing directly the antenna line track.
• Avoid crossing any un-shielded transmission line footprint with other signal tracks on different layers;
• The ground surrounding the antenna line on PCB has to be strictly connected to the main Ground
Plane by means of via holes (once per 2mm at least), placed close to the ground edges facing line
track;
• Place EM noisy devices as far as possible from ME910C1 antenna line;
• Keep the antenna line far away from the ME910C1 power supply lines;