User's Manual

LE920 Hardware User Guide
1vv0301026 Rev.8 2015-01-03
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Furthermore if the device is developed for the US and/or Canada market, it must comply with
the FCC and/or IC requirements.
This device is to be used only for mobile and fixed application.
6.5.4. GPS/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 tracks directly facing the antenna line track.
 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 LE920 antenna line.
 Keep the antenna line far away from the LE920 power supply lines.
 If EM-noisy devices are around the PCB hosting the LE920, 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 LE920, use a Micro strip line
on the surface copper layer for the antenna line. The line attenuation will be lower than a
buried one.
6.5.5. GPS/GNSS Antenna – Installation Guidelines
 The LE920, 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)
 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.
 The antenna shall also be installed according to the antenna manufacturer’s instructions.