NRF9160: GPS Tracking satellites, but can't get fix.

[mlang3440]

Hi, we have a custom board using the nrf9160, running modem firmware 1.1, and using the nrf9160_gps driver.

Sometimes we see messages like this:

Tracking: 8 Using: 0 Unhealthy: 0

Where the GPS is tracking satellites but is not using any, and never gets a fix. Eventually we time-out and stop the GPS. But this behavior continues until the next device is restarted.

Is this a bug with the modem firmware? Is there any fix for this.

Thanks

[jwhite]

I am having almost exactly the same issue, but with an out-of-the-box nRF9160DK running the GPS example with NCS v1.2. Since there is no verified answer here, I will present my question here. Here is my setup:

I received a nRF9160DK two weeks ago, and I was able to get it up and running with the Asset tracker firmware, and I was also able to get the GPS example working after flashing it from SES. After about 30-60 seconds, the gps example would get a fix and start printing out the nmea data on the nRF connect link monitor. I was able to get a fix indoors with the patch antenna provided.

But now, when I start up the nRF9160DK running the GPS example, it sits and prints out that it sees anywhere from 6-9 satellites, but it never finds a fix. I have let it sit for hours to no avail. I am not using the SUPL library because I want to run the GPS without LTE active. I've also tried going outside, switching from the onboard antenna to the external antenna, and restarting/re-programming the application. I seem to be stuck in the case that mlang said, but I never get out of it. Is there anything else I can try for this issue?

Here is a screenshot of the link monitor while the GPS example is running:

[Øyvind]

Hello jwhite,

What modem version are you running? Have you tested it outside in the open?

As stated in the nRF9160 DK documentation:
"GPS signals do not usually penetrate ceilings or other structures that well. Therefore, for best GPS performance, the DK should be placed on a flat surface in an open space outside, far from sources of interference and other structures that may block the signals from space."

If you are experiencing more issues, please register a new ticket regarding your issue.

Kind regards,
Øyvind

[RicardoPereira]

Hi, 

I'm having the same issues as jwhite  with my thingy:91.

I can get up to 9 tracking but never get fix. I have the firmware 1.2.0. 

Any ideas ?

Regards, 

[jwhite]

RicardoPereira I was having this issue indoors, using a large passive GPS antenna. I moved my nrf9160dk closer to my window and it was able to get a fix only using 5 satellites within 45 seconds. I never got an answer as to why a fix could not be found using 9 satellites, and I could not find a forum post that digs farther into this issue.