BG95 GPS only reporting SBAS PRNs

IoT Modules GNSS Module
1

One of our devices in the British Virgin Islands is unable to make a GPS fix, and is only reporting SBAS PRNs as shown in the NMEA output below. Could you suggest what might cause this situation ? Thanks.

$GPGSV,3,1,11,33,,,34,38,,,34,39,,,34,40,,,35,1*62
$GPGSV,3,2,11,41,,,34,42,,,34,46,,,34,48,,,35,1*69
$GPGSV,3,3,11,49,,,34,50,,,34,51,,,34,1*6F
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N,V*29
$GPGSV,3,1,11,33,,,34,38,,,34,39,,,34,40,,,35,1*62
$GPGSV,3,2,11,41,,,34,42,,,34,46,,,34,48,,,35,1*69
$GPGSV,3,3,11,49,,,34,50,,,34,51,,,34,1*6F
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N,V*29
$GPGSV,3,1,11,33,,,34,38,,,34,39,,,34,40,,,35,1*62
$GPGSV,3,2,11,41,,,34,42,,,34,46,,,34,48,,,35,1*69
$GPGSV,3,3,11,49,,,34,50,,,34,51,,,34,1*6F
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N,V*29
$GPGSV,3,1,11,33,,,34,38,,,34,39,,,34,40,,,35,1*62
$GPGSV,3,2,11,41,,,34,42,,,34,46,,,34,48,,,35,1*69
$GPGSV,3,3,11,49,,,34,50,,,34,51,,,34,1*6F
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N,V*29
$GPGSV,3,1,11,33,,,34,38,,,34,39,,,34,40,,,35,1*62
$GPGSV,3,2,11,41,,,34,42,,,34,46,,,34,48,,,35,1*69
$GPGSV,3,3,11,49,,,34,50,,,34,51,,,34,1*6F
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N,V*29
2

Hi Sdt99
How long has the GNSS of the device been powered on? GNSS positioning generally takes more than 30 seconds. You can test the device in an outdoor environment with good signal. If you still can’t locate it, please provide the NMEA log for a longer locating from the GNSS power supply. The log you provided this time is too small for analysis. Thank you!

3

Hi Albert, The GNSS had been powered on for over 5 minutes at the time the log was captured. I will see if I can get a longer log, but the device is remote to me so I will need to work with our customer. Thank you.

4

Hi Sdt99
The signal strength is only 34db, please go to the outdoor open sky to test or check the antenna.Thank you!

5

Hi Sean,

You CN levels are quite low. Have you had the antenna tuning checked. We offer free testing services that also include active GNSS testing and tuning for optimizing devices to their best potential. We can also steer you to the optimal antenna solution for your device. Please feel free to contact me on Chris@synzen.com.tw