Just as a last ditch effort, have you tried disconnecting the external GPS puck antenna and let the internal patch antenna take over? Perhaps we may have better luck with that due to the external antenna not amplifing the noise anymore. Just a thought.
Thanks,
Sriram
without an antenna connected i have this result
Internal GPS Latitude
40.82742 degrees
Internal GPS Longitude
16.54866 degrees
Internal GPS Height
483.3 meters
GPS time (Greenwich Mean Time)
13:06:03
GPS Firmware Version
AXN_1.51_2838
Satellites Tracked
5
Satellites Visible
14
but if i active the gps sync i still have no signal
How are the SNR levels on the satellites? Tracking four satellites should be enough but I am not sure if it is consistently tracking 4 or more. To get a good 3D lock, the SNR should be 25 or more. Are you seeing that?
Have you made sure of the following:
- Under the Configuration->Radio page, under the Scheduler section, you have either 75/25, 50/50 or 30/70 option selected. The Flexible option cannot be used with GPS Sync.
- Under the Configuration->Radio page, under the Synchronization section, the Syncronization option is set to GPS.
- In the Home page, Sync Source Status shows GPS Sync Up
How are the SNR levels on the satellites? Tracking four satellites should be enough but I am not sure if it is consistently tracking 4 or more. To get a good 3D lock, the SNR should be 25 or more. Are you seeing that?
Have you made sure of the following:
- Under the Configuration->Radio page, under the Scheduler section, you have either 75/25, 50/50 or 30/70 option selected. The Flexible option cannot be used with GPS Sync.
- Under the Configuration->Radio page, under the Synchronization section, the Syncronization option is set to GPS.
- In the Home page, Sync Source Status shows GPS Sync Up
Thanks,
Sriram
the SNR is about 19/20/28/17 of the 4 satellites received.
But this is only for the night hours, during the day i do not receive signal from gps, the gps received is 0 or max 1 (this without an external antenna connected).
Anyway the BTS umts on the same roof work at 1.8/2.1 ghz and 800mhz.
Anyway the BTS umts on the same roof work at 1.8/2.1 ghz and 800mhz.
Hi Guiseppe,
This is a good clue. The UMTS radio at 1.8 GHz is uncomfortably close to the GPS freq of 1.4 GHz. We have seen this exact same problem with another customer with an UMTS repeater on the same roof. I suspect that's what is wiping out the GPS receiver. Do you have the ability to scan the band with a portable spectrum analyzer? A scan of 1.4 GHz will tell us if it is indeed the UMTS BTS.