Please help 'Getting all SV position and SNR'

jeongho.public · July 10, 2024, 2:11am

Hi there,

I am trying to retrieve all SV positions and SNR from my measurements, even though the data quality is low. To achieve this, my RS2 receiver logs measurements in UBX format. I convert UBX to RINEX format using Emlid Flow, and then I obtain SV positions and SNR from the measurements through teqc +qc +plot post-processing.

However, there are some issues with the teqc qc results for SV positions and SNR. My SV position file (.ele, .azi) contains only GPS (G) and GLONASS (R) positions, even though the SV SNR file (.sn1) includes information for all SVs (GPS (G), GLONASS (R), SBAS (S), Galileo (E), BeiDou (C), and QZSS (J)). Despite this, the Emlid Flow skyplot figure shows all SV positions (please check below two figure).

So, here are my questions:

Do you know why the SV position file from teqc (.ele and .azi) includes only G and R information, even though the sn1 file includes information for all SVs (GPS (G), GLONASS (R), SBAS (S), Galileo (E), BeiDou (C), and QZSS (J))?
My goal is to obtain all SVs’ SNR and positions during the measurement period. Are there any specific settings for the RS2 to maximize the number of GNSS SV positions with SNR information?
How can I retrieve all SV positions with SNR information from my UBX file? Do I need to add specific commend for teqc, or should I use another way to achieve my goal?

For better understanding, I have attached my sample measurement dataset and teqc commands.

Link for system report:

Link for BNX file:

Link for RINEX and TEQC result:

teqc commend:
$ teqc +qc +plot ++rx_state rx_state path_to_input_file

teqc qc result summary:
version: teqc 2019Feb25

SV±------|--------|--------|--------|--------|--------|--------|--------|-+ SV

QC of RINEX file(s) : F:\gnss_vod\RINEX\upper\rinex_Upper_raw_20240607032908\Upper_raw_20240607032908.24O
input RnxNAV file(s) : F:\gnss_vod\RINEX\upper\rinex_Upper_raw_20240607032908\Upper_raw_20240607032908.24N
F:\gnss_vod\RINEX\upper\rinex_Upper_raw_20240607032908\Upper_raw_20240607032908.24G
F:\gnss_vod\RINEX\upper\rinex_Upper_raw_20240607032908\Upper_raw_20240607032908.24H
F:\gnss_vod\RINEX\upper\rinex_Upper_raw_20240607032908\Upper_raw_20240607032908.24C

4-character ID : Uppe
Receiver type :
Antenna type :

Time of start of window : 2024 Jun 7 03:29:40.003
Time of end of window : 2024 Jun 8 03:29:30.006
Time line window length : 24.00 hour(s), ticked every 3.0 hour(s)
mean antenna; # of pos : 118
antenna WGS 84 (xyz) : -3049513.4402 4025039.2442 3883614.9811 (m)
antenna WGS 84 (geo) : N 37 deg 44’ 55.27" E 127 deg 08’ 55.93"
antenna WGS 84 (geo) : 37.748687 deg 127.148869 deg
WGS 84 height : 309.6543 m
|qc - header| position : 14.3881 m
qc position offsets : 14.3270 m vertical 1.3243 m horizontal
Observation interval : 10.0000 seconds
Total satellites w/ obs : 112
NAVSTAR GPS unhealthy SV: 1
NAVSTAR GPS SVs w/o OBS :
NAVSTAR GPS SVs w/o NAV :
GLONASS unhealthy SV: 10 24
GLONASS SVs w/o OBS :
GLONASS SVs w/o NAV :
SBAS unhealthy SV: 28
SBAS SVs w/o OBS : 20 21 22 23 24 25 26 27 28 29 30 31
32 33 34 35 36 37 38 39 40 41 42 43 44
45 46 48 49 50 51 52 53 54 55 57 58
SBAS SVs w/o NAV :
Galileo SVs w/o OBS : 1 16 17 20 22 23 28 32 35 37 38 39
40 41 42 43 44 45 46 47 48 49 50 51 52
53
Galileo SVs w/o NAV : 7 12 24 26 29 31 33 10 19 11 4 14
9 36 6 5 34 3 25 2 8 30 15 27 18
13 21
Beidou SVs w/o OBS : 1 2 3 4 5 15 17 18 31 32 33 34
35 37
Beidou SVs w/o NAV : 7 8 10 13 20 27 29 30 19 22 12 16
6 21 9 11 26 14 24 25 23 28 36
QZSS SVs w/o OBS : 1 5 6 8 9 10
QZSS SVs w/o NAV : 2 3 4 7
Rx tracking capability : unknown
Poss. # of obs epochs : 8640
Epochs w/ observations : 8639
Epochs repeated : 0 (0.00%)

===< MP71 RMS summary (per SV):
slips L1 rx SV obs>10 E07* 1623 E12* 2519 E24* 3482 E26* 792 E31* 2671 E33* 1776 C07* 5692 5692 C08* 5675 5675 C10* 5348 5348 C13* 5533 5533 E10* 3498 E19* 2378 1581 E11* 3631 1640 E04* 3011 E14* 2970 C12* 3123 3123 E09* 3255 E36* 3860 C16* 5837 5837 C06* 5820 5820 C09* 5698 5698 C11* 2931 2931 E05* 3428 E34* 3723 C14* 2871 2871 E03* 2985 E25* 3051 E02* 3241 E08* 2068 E30* 2882 E15* 1942 E27* 1921 E18* 1883 E13* 1138 E21* 864 *** = SV /em>=============
L7 rx slips L1 rx L7 rx
# del MP71 rms [m] < 25 < 25 < 25 > 25 > 25 > 25
461 0.00 0.788166 0 1 0 0 0 0
484 0.00 0.880239 1 1 0 0 0 0
737 0.00 1.019560 1 6 0 0 0 0
757 0.00 0.814037 1 7 0 0 0 0
752 0.00 1.666199 2 1 0 0 0 0
388 0.00 0.781275 1 0 0 0 0 0
0.00 0.317117 0 3 0 0 0 0
0.00 0.432087 0 1 0 0 0 0
0.00 0.384208 2 2 0 0 0 0
0.00 0.592587 5 1 0 0 0 0
516 0.00 1.034820 0 2 0 0 0 0
0.00 1.221925 5 5 0 0 0 0
0.00 1.060779 0 4 0 0 0 0
848 0.00 1.137933 3 6 0 0 0 0
660 0.00 1.514418 1 5 0 0 0 0
0.00 0.533546 2 5 0 0 0 0
286 0.00 1.535364 1 1 0 0 0 0
645 0.00 0.780128 1 2 0 0 0 0
0.00 0.331263 0 1 0 0 0 0
0.00 0.338812 0 2 0 0 0 0
0.00 0.535211 6 1 0 0 0 0
0.00 0.756362 5 3 0 0 0 0
627 0.00 0.862127 0 3 0 0 0 0
567 0.00 0.817484 0 2 0 0 0 0
0.00 0.769052 4 8 0 0 0 0
458 0.00 0.893515 1 3 0 0 0 0
742 0.00 1.550142 3 3 0 0 0 0
236 0.00 1.344894 0 1 0 0 0 0
111 0.00 1.000234 0 1 0 0 0 0
131 0.00 1.231694 0 0 0 0 0 0
33 0.00 0.635256 0 0 0 0 0 0
25 0.00 0.800103 0 3 0 0 0 0
18 0.00 0.753281 0 0 0 0 0 0
37 0.00 0.649837 0 0 0 0 0 0
5 0.00 0.506802 0 0 0 0 0 0
with no NAV info (or not being used)**

image849×646 194 KB

image1395×453 14.1 KB

kornel.nemeti · July 12, 2024, 9:25am

Hi @jeongho.public,

Thank you for your questions!

It’s hard to determine for sure why not all the satellite constellations are included in these result files. I checked your raw data from Reach, and the logs have been recorded properly, so everything seems fine on Reach’s side.

If I understand correctly, only the .ele and .azi files don’t contain all the constellations. Is there a chance the app’s limitation is that it includes only GPS and GLONASS in these files?

jeongho.public · July 17, 2024, 7:26am

Thank you for your answer, @kornel.nemeti

I am not sure if it is a limitation of the app (I guess the app you mentioned is ‘TEQC’). I also checked and there is no issue with the UBX file.

Is there any way to retrieve all SV positions (ele, azi) and SNR from the UBX file?

kornel.nemeti · July 22, 2024, 4:44pm

Hi @jeongho.public,

Yes, I supposed that maybe the TEQC has some kind of limitations. Our receivers output the standard RINEX formats without any modification in its content. Still, it’s hard to determine how third-party software handles all these information.

EBE111057 · July 22, 2024, 5:18pm

Teqc is no longer supported for development or updates. The last version issued was in 2019.

See