<div dir="ltr">try to rule out real-time issues <div>by saving the data streams as </div><div>files on disk and post-processing</div><div>using the rtkpost GUI instead of the </div><div>rtkrcv CUI. ask it to save residuals</div><div>and inspect them graphically using </div><div>rtkplot.</div><div>-F.</div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Sep 17, 2015 at 4:00 PM, <span dir="ltr"><<a href="mailto:foss-gps-request@lists.osgeo.org" target="_blank">foss-gps-request@lists.osgeo.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Message: 1<br>
Date: Thu, 17 Sep 2015 12:37:59 +1200<br>
From: Dean Ashby <<a href="mailto:dean@ashby.org.nz">dean@ashby.org.nz</a>><br>
To: <a href="mailto:foss-gps@lists.osgeo.org">foss-gps@lists.osgeo.org</a><br>
Subject: [FOSS-GPS] Problem with RTKLIB kinematic, large residual,<br>
slip detected, ambiguity validation failed<br>
Message-ID: <<a href="mailto:55FA0B67.3030503@ashby.org.nz">55FA0B67.3030503@ashby.org.nz</a>><br>
Content-Type: text/plain; charset="utf-8"<br>
<br>
Hi,<br>
<br>
I'm relatively new to RTKLIB but have done quite a bit of reading over<br>
the past few weeks so please bear with me if I've missed something obvious.<br>
<br>
When running rtkrcv in kinematic mode talking to a base station running<br>
str2str via tcpcli I very rarely get a FIXED solution, usually it's just<br>
a FLOATING solution.<br>
<br>
I see a lot of this:<br>
<br>
rtkrcv> error<br>
00:17:18.00: slip detected (sat=14 rcv=1 LLI1=3)<br>
00:17:18.00: slip detected (sat=25 rcv=1 LLI1=3)<br>
00:17:18.00: ambiguity validation failed (nb=6 ratio=1.44 s=25.24/36.30)<br>
00:17:19.00: slip detected (sat=14 rcv=1 LLI1=3)<br>
00:17:19.00: slip detected (sat=16 rcv=1 LLI1=3)<br>
00:17:19.00: slip detected (sat=25 rcv=1 LLI1=3)<br>
00:17:19.00: ambiguity validation failed (nb=6 ratio=1.45 s=29.42/42.56)<br>
00:17:20.00: slip detected (sat=25 rcv=1 LLI1=3)<br>
00:17:20.00: ambiguity validation failed (nb=6 ratio=1.46 s=31.24/45.48)<br>
00:17:21.00: slip detected (sat=16 rcv=1 LLI1=3)<br>
00:17:21.00: slip detected (sat=25 rcv=1 LLI1=3)<br>
00:17:21.00: ambiguity validation failed (nb=6 ratio=1.45 s=34.00/49.20)<br>
00:17:22.00: slip detected (sat=14 rcv=1 LLI1=3)<br>
00:17:22.00: slip detected (sat=25 rcv=1 LLI1=3)<br>
00:17:22.00: ambiguity validation failed (nb=6 ratio=1.31 s=37.35/49.06)<br>
<br>
<br>
I've seen various other posts where people have had similar problems but<br>
that has ofte been put down to cheap patch antennas and poor SNR.<br>
Admittedly I'm using cheapish active patch antennas sitting on sheets of<br>
spare 3mm aluminium to act as ground planes, located in reasonably clear<br>
space on three sides, and the satellite SNR looks OK:<br>
<br>
rtkrcv> obs<br>
<br>
TIME(GPST) SAT R P1(m) P2(m) L1(cyc) L2(cyc)<br>
D1(Hz) D2(Hz) S1 S2 LLI<br>
00:17:55.0 G01 1 23173440.00 0.00 -67934004.25 0.00<br>
4321.2 0.0 42 0 2 0<br>
00:17:55.0 G03 1 20996503.04 0.00 -80470547.61 0.00<br>
8531.9 0.0 43 0 2 0<br>
00:17:55.0 G04 1 23901429.65 0.00 -56298544.87 0.00<br>
3864.9 0.0 44 0 2 0<br>
00:17:55.0 G14 1 23016147.60 0.00 -48310509.64 0.00<br>
3804.7 0.0 35 0 2 0<br>
00:17:55.0 G16 1 23683356.32 0.00 -27092194.48 0.00<br>
10341.1 0.0 32 0 2 0<br>
00:17:55.0 G22 1 25079322.86 0.00 -38665003.76 0.00<br>
2944.1 0.0 28 0 3 0<br>
00:17:55.0 G23 1 22642174.23 0.00 -44392777.77 0.00<br>
9568.9 0.0 47 0 2 0<br>
00:17:55.0 G25 1 23260380.39 0.00 -70004514.13 0.00<br>
4404.1 0.0 30 0 3 0<br>
00:17:55.0 G26 1 21612855.57 0.00 -63585920.57 0.00<br>
9476.4 0.0 45 0 2 0<br>
00:17:55.0 G31 1 19896070.95 0.00 -79557949.56 0.00<br>
5677.5 0.0 44 0 2 0<br>
00:17:55.0 G32 1 19775470.02 0.00 -84790957.79 0.00<br>
6361.9 0.0 49 0 2 0<br>
<br>
00:17:55.0 G01 2 23428649.54 0.00 123118157.28 0.00<br>
0.0 0.0 42 0 0 0<br>
00:17:55.0 G03 2 21251709.44 0.00 111677473.40 0.00<br>
0.0 0.0 48 0 0 0<br>
00:17:55.0 G04 2 24156636.48 0.00 126942627.26 0.00<br>
0.0 0.0 41 0 0 0<br>
00:17:55.0 G14 2 23271350.71 0.00 122291627.81 0.00<br>
0.0 0.0 33 0 0 0<br>
00:17:55.0 G16 2 23938559.50 0.00 125797319.77 0.00<br>
0.0 0.0 43 0 0 0<br>
00:17:55.0 G22 2 25334523.53 0.00 133133154.17 0.00<br>
0.0 0.0 26 0 1 0<br>
00:17:55.0 G23 2 22897381.47 0.00 120326137.93 0.00<br>
0.0 0.0 49 0 0 0<br>
00:17:55.0 G25 2 23515585.12 0.00 123575137.32 0.00<br>
0.0 0.0 29 0 1 0<br>
00:17:55.0 G26 2 21868061.88 0.00 114917375.21 0.00<br>
0.0 0.0 44 0 0 0<br>
00:17:55.0 G31 2 20151273.77 0.00 105894595.55 0.00<br>
0.0 0.0 51 0 0 0<br>
00:17:55.0 G32 2 20030674.09 0.00 105260781.87 0.00<br>
0.0 0.0 47 0 0 0<br>
<br>
There are a few things here that seem unusual though. My understanding<br>
is that the first block of satellites are from the local (serial) GPS<br>
receiver and the second block are from the base station. The P and L<br>
values seem to significantly different, and the doppler (D) values don't<br>
exist for the base station. This strikes me as very odd as I have seem<br>
some other examples on-line where these values are much closer matches.<br>
<br>
Rtkrcv appears to be receiving RTCM messages from the base station<br>
according to the status output:<br>
<br>
rtkrcv> sta<br>
<br>
Parameter : Value<br>
rtklib version : 2.4.2<br>
rtk server thread : -1227946896<br>
rtk server state : run<br>
processing cycle (ms) : 100<br>
positioning mode : kinematic<br>
frequencies : L1<br>
accumulated time to run : 00:28:52.7<br>
cpu time for a cycle (ms) : 45<br>
missing obs data count : 0<br>
bytes in input buffer : 0,0<br>
# of input data rover :<br>
obs(1732),nav(24),gnav(0),ion(657),sbs(3431),pos(0),dgps(0),ssr(0),err(0)<br>
# of input data base :<br>
obs(1733),nav(25),gnav(0),ion(0),sbs(0),pos(114),dgps(0),ssr(0),err(0)<br>
# of input data corr :<br>
obs(0),nav(0),gnav(0),ion(0),sbs(0),pos(0),dgps(0),ssr(0),err(0)<br>
# of rtcm messages rover :<br>
# of rtcm messages base :<br>
1002(1733),1004(1733),1005(57),1006(57),1019(670)<br>
# of rtcm messages corr :<br>
solution status : float<br>
time of receiver clock rover: 2015/09/17 00:25:50.000480056<br>
time sys offset (glo-gps)(s): 0.000000000<br>
solution interval (s) : 1.000<br>
age of differential (s) : 0.001<br>
ratio for ar validation : 1.160<br>
# of satellites rover : 11<br>
# of satellites base : 10<br>
# of valid satellites : 10<br>
GDOP/PDOP/HDOP/VDOP : 1.6,1.5,0.8,1.2<br>
# of real estimated states : 3<br>
# of all estimated states : 124<br>
pos xyz single (m) rover : -4603225.267,603993.316,-4358763.701<br>
pos llh single (deg,m) rover: -43.38549245,172.52487221,56.564<br>
vel enu (m/s) rover : 0.062,-0.092,-0.162<br>
pos xyz float (m) rover : -4603225.267,603993.316,-4358763.701<br>
pos xyz float std (m) rover : 0.233,0.137,0.204<br>
pos xyz fixed (m) rover : -4603228.149,604003.890,-4358765.385<br>
pos xyz fixed std (m) rover : 0.038,0.049,0.022<br>
pos xyz (m) base : -4603224.437,603994.410,-4358758.516<br>
ant type rover :<br>
ant delta rover : 0.000 0.000 0.000<br>
ant type base :<br>
ant delta base : 0.000 0.000 0.000<br>
pos llh (deg,m) base : -43.38546274,172.52485749,52.507<br>
vel enu (m/s) base : 0.000,0.000,0.000<br>
baseline length float (m) : 5.365<br>
baseline length fixed (m) : 12.282<br>
monitor port : 0<br>
<br>
I can supply my configs and more information about the hardware and<br>
software version if necessary but this message was getting large enough<br>
as it was and I thought the information above might be enough to<br>
diagnose what I am missing.<br>
<br>
Any help much appreciated.<br>
<br>
Regards,<br>
<br>
Dean<br>
<br>
-------------- next part --------------<br>
A non-text attachment was scrubbed...<br>
Name: dean.vcf<br>
Type: text/x-vcard<br>
Size: 167 bytes<br>
Desc: not available<br>
URL: <<a href="http://lists.osgeo.org/pipermail/foss-gps/attachments/20150917/fcf857fb/attachment-0001.vcf" rel="noreferrer" target="_blank">http://lists.osgeo.org/pipermail/foss-gps/attachments/20150917/fcf857fb/attachment-0001.vcf</a>><br>
<br>
------------------------------<br>
<br>
_______________________________________________<br>
FOSS-GPS mailing list<br>
<a href="mailto:FOSS-GPS@lists.osgeo.org">FOSS-GPS@lists.osgeo.org</a><br>
<a href="http://lists.osgeo.org/mailman/listinfo/foss-gps" rel="noreferrer" target="_blank">http://lists.osgeo.org/mailman/listinfo/foss-gps</a><br>
<br>
End of FOSS-GPS Digest, Vol 80, Issue 9<br>
***************************************<br>
</blockquote></div><br></div></div>