NEO-M8P - Hardware Integration Manual
UBX-15028081 - R05
Early Production Information
Design
Page 13 of 27
Use an antenna that has sufficient bandwidth to receive all GNSS constellations. See Appendix A.1.
Figure 7 shows a design using an external LNA to increase the sensitivity for best performance with passive
antenna.
Figure 7: Module design with passive antenna and an external LNA (for exact pin orientation see the
NEO-M8P Data Sheet
The
LNA_EN
pin (LNA enable) can be used to turn on and off an optional external LNA.
The
VCC_RF
output can be used to supply the LNA with a filtered supply voltage.
Ensure the LNA has enough bandwidth to amplify all the required satellite signals.
An external LNA is only required if the antenna is far away. In that case the LNA has to be placed close to
the passive antenna.
Add a SAW filter before or after the LNA to prevent any blocking issues from out-of-band signals
2.4.2
Active antenna design
Active antennas have an integrated low-noise amplifier. Active antennas require a power supply that will contribute
to the total GNSS system power consumption budget with additional 5 to 20 mA typically.
If the supply voltage of the NEO-M8 receiver matches the supply voltage of the antenna (e.g. 3.0 V), use the
filtered supply voltage
available at pin
VCC_RF
as shown in Figure 8.
Active antenna design using VCC_RF pin to supply the active antenna
