mhostetter
commented
4 years ago Sorry for the late reply.
- The messages that faile to decode with something like
CRC: Failed (PI-CRC = -3883480)are due to low SNR. That is to be expected. - The
Datetime: 2020-01-15 18:28:00.954059 UTCfields are from system time, not the GPSDO time. You would need to modify the framer to grab the USRP stream tags to correlate GPS time and absolute sample offset. That could then be used to convert frame start-of-burst sample into true GPS time. That shouldn't be too hard, and I'm open to pull requests 😃 - The time syncing issue you are referring is not an issue. The
Time: 0 Not Synced to 0.2s UTC Epochoutput is decoded from the ADS-B packet. It means that the ADS-B timestamps from the ADS-B hardware are not synced to 0.2s UTC time. - The
OOOOOOOOOOoutputs you are getting are from overruns from your USRP hardware. This will likely cause some packets to get decoded incorrectly. Ideally, run you USRP at the lowest rate possible, with 2 Msps being the lowest.
sdradsb
Hi , I am a graduate student and I am using gr-adsb to capture the adsb signals but I am facing some trouble. If you could guide me on this it would be really helpful.
When i used gr-adsb this is the verbose that I got:
Gtk-Message: 12:27:46.224: Failed to load module "canberra-gtk-module" [INFO] [UHD] linux; GNU C++ version 7.4.0; Boost_106501; UHD_3.14.1.HEAD-0-gbfb9c1c7 [INFO] [B200] Detected Device: B210 [INFO] [B200] Operating over USB 3. [INFO] [B200] Detecting internal GPSDO.... [INFO] [GPS] Found an internal GPSDO: GPSTCXO, Firmware Rev 0.929b [INFO] [B200] Initialize CODEC control... [INFO] [B200] Initialize Radio control... [INFO] [B200] Performing register loopback test... [INFO] [B200] Register loopback test passed [INFO] [B200] Performing register loopback test... [INFO] [B200] Register loopback test passed [INFO] [B200] Setting master clock rate selection to 'automatic'. [INFO] [B200] Asking for clock rate 16.000000 MHz... [INFO] [B200] Actually got clock rate 16.000000 MHz. [INFO] [B200] Asking for clock rate 32.000000 MHz... [INFO] [B200] Actually got clock rate 32.000000 MHz. OOOOO
Datetime: 2020-01-15 18:27:50.463353 UTC SNR: 14.45 dB DF: 17 Extended Squitter CRC: Passed CA: 5 Level 2 or Above Transponder, Can Set CA 7, In Air AA: a82298 TC: 4 Identification (Category Set A) Callsign: NKS250
OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Datetime: 2020-01-15 18:27:52.824349 UTC SNR: 12.14 dB DF: 17 Extended Squitter CRC: Passed CA: 5 Level 2 or Above Transponder, Can Set CA 7, In Air AA: ac491d TC: 29 Reserved To be implemented OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Datetime: 2020-01-15 18:27:54.682372 UTC SNR: 6.92 dB DF: 17 Extended Squitter CRC: Failed (PI-CRC = -858354) OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Datetime: 2020-01-15 18:27:59.115507 UTC SNR: 5.36 dB DF: 17 Extended Squitter CRC: Failed (PI-CRC = -3883480) OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Datetime: 2020-01-15 18:28:00.954059 UTC SNR: 14.87 dB DF: 17 Extended Squitter CRC: Passed CA: 5 Level 2 or Above Transponder, Can Set CA 7, In Air AA: a82298 TC: 11 Airborne Position valid_lat_lon False lat_cpr 92136 lon_cpr 58629 lat nan lon nan SS: 0 No Condition Information Time: 0 Not Synced to 0.2s UTC Epoch Latitude: N/A N Longitude: N/A E Altitude: 34000 ft OOOOOOOOOOO
*In the above output it shows that some messages have been failed to display. I still am unable to figure out why I get failed messages.
*I have an internal GPSDO installed. So is the timestamp displayed aligned with the GPSDO? (my B210 and GPSDO time was aligned earlier)
*For the last message, it is shown that time is not synced and it also doesn't display the corresponding latitude and longitude. Is there way I could print out the corresponding lat/long for each message (position reports) as well.
Thank you