I have problem with internal LNA. On the output GPS RF connector is’nt voltage.
Can You help me ?
Have you investigated with related AT commands, AT$GPSAT, AT$GPSP, AT$GPSPS ?
AT$GPSAT?
$GPSAT: 0
OK
Internal LNA is used
AT$GPSP?
$GPSP: 1
OK
SiRF Star IV is turned on
AT$GPSPS?
$GPSPS: 0,1800
OK
Power saving is disabled
AT$GPSAT should be 1. From Telit GPS User Guide, 4.5 GPS Antenna Power Supply:
Check if the GPS antenna is supplied by the module itself: 1 means that the GPS antenna is supplied by the module.
AT$GPSAT? $GPSAT: 1 OK
Sorry, but in Telit_GPS_User_Guide_r1 (1).pdf, section 4.6 External LNA is write:
For GE864-GPS module the AT$GPSAT command has a different functionality compared with the same command running on GM862-GPS and GE863-GPS modules.
GE864-GPS is provided with a SiRF Star IV GPS chipset. The chipset is equipped with an internal LNA, if the user needs an external LNA having a better gain than the internal one, he may disable the internal LNA using the AT$GPSAT command.
AT$GPSAT=1 Enable external LNA
I have not implemented external LNA.
If you are using an active antenna the external LNA is built-in so you need AT$GPSAT=1.
If your antenna is passive use AT$GPSAT=0, no power voltage at the antenna connector.
Power Voltage is’nt present with both AT commands. e.g. AT$GPSAT=1 or AT$GPSAT=0.
Maibe i have a hardware problem.
Output GPS Antenna ball A10 is connected directly to RF connector, without other components, like inductor and capacitor connected to ground.
I have problem with internal LNA. On the output GPS RF connector is’nt voltage.
Can You help me ?
Have you investigated with related AT commands, AT$GPSAT, AT$GPSP, AT$GPSPS ?
AT$GPSAT should be 1. From Telit GPS User Guide, 4.5 GPS Antenna Power Supply:
Sorry, but in Telit_GPS_User_Guide_r1 (1).pdf, section 4.6 External LNA is write:
For GE864-GPS module the AT$GPSAT command has a different functionality compared with the same command running on GM862-GPS and GE863-GPS modules.
GE864-GPS is provided with a SiRF Star IV GPS chipset. The chipset is equipped with an internal LNA, if the user needs an external LNA having a better gain than the internal one, he may disable the internal LNA using the AT$GPSAT command.
AT$GPSAT=1 Enable external LNA
I have not implemented external LNA.
If you are using an active antenna the external LNA is built-in so you need AT$GPSAT=1.
If your antenna is passive use AT$GPSAT=0, no power voltage at the antenna connector.
Power Voltage is’nt present with both AT commands. e.g. AT$GPSAT=1 or AT$GPSAT=0.
Maibe i have a hardware problem.
Output GPS Antenna ball A10 is connected directly to RF connector, without other components, like inductor and capacitor connected to ground.