User's Guide
xE922-3GR Hardware User Guide
1VV0301272 Rev.0.8 2017-01-05
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16.3.4. GNSS Antenna - PCB Line Guidelines
· Ensure that the antenna line impedance is 50ohm.
· Keep the line on the PCB as short as possible to reduce the loss.
· The antenna line must have uniform characteristics, constant cross section, avoiding
meanders and abrupt curves.
· Keep one layer of the PCB used only for the Ground plane; if possible.
· Surround (on the sides, over and under) the antenna line on the PCB with Ground. Avoid
having other signal traces in proximity of the transmission line where coupling may occur.
· The Ground around the antenna line on the PCB must be strictly connected to the main
Ground plane by placing vias at least once per 2mm.
· Place EM-noisy devices as far as possible from xE922-3GR antenna line.
· Keep the antenna line far away from the xE922-3GR power supply lines.
· If EM-noisy devices are around the PCB hosting the xE922-3GR, such as fast switching
ICs, ensure shielding the antenna line by burying it inside the layers of PCB and
surrounding it with Ground planes; or shield it with a metal frame cover.
· If you do not have EM-noisy devices around the PCB of xE922-3GR, use a Micro strip line
on the surface copper layer for the antenna line. The line attenuation will be lower than a
buried one.
16.3.5. GNSS Antenna – Installation Guidelines
· The xE922-3GR, due to its sensitivity characteristics, is capable of performing a fix inside
buildings. (In any case the sensitivity could be affected by the building characteristics i.e.
shielding)
· If the chosen antenna is a style which requires a ground plane, ensure that it is properly
attached, both electrically and mechanically, to a ground plane with dimensions and
mechanical structure as recommended by the antenna manufacturer
· The antenna must not be co-located or operating in conjunction with any other antenna or
transmitter.
· The antenna shall not be installed inside metal cases.