<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>I mean instantaneous , not simultaneous .<br><br>Kind regards,<div>Yanqing</div></div><div><br>On 17 Sep 2014, at 23:05, "Sean Hyde" <<a href="mailto:sean.a.hyde@gmail.com">sean.a.hyde@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"><meta name="Generator" content="Microsoft Word 15 (filtered medium)"><!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
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</o:shapelayout></xml><![endif]--><div class="WordSection1"><p class="MsoNormal">Hey Guys,<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">I’ve been playing around with RTKLib for a couple months now and have run into some issues and I was wondering if anyone had any idea on how to improve performance.<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">---Setup---<o:p></o:p></p><p class="MsoNormal">Base Station:<o:p></o:p></p><p class="MsoNormal">NVS08C on custom PCB using the receiver to power the antenna<o:p></o:p></p><p class="MsoNormal">Antenna is Taoglas Limited AA.161.301111 (<a href="http://www.taoglas.com/images/product_images/original_images/AA.161.301111.pdf">http://www.taoglas.com/images/product_images/original_images/AA.161.301111.pdf</a>)<o:p></o:p></p><p class="MsoNormal">Antenna is on a 12” x 24” steel plate<o:p></o:p></p><p class="MsoNormal">Connected via FTDI->USB to Rasperry Pi<o:p></o:p></p><p class="MsoNormal">Raspberry Pi runs str2str to send the data to Windows laptop running rtknavi using wifi backhaul<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">Rover:<o:p></o:p></p><p class="MsoNormal">NVS08C on custom PCB using the receiver to power the antenna<o:p></o:p></p><p class="MsoNormal">Antenna is Taoglas Limited AA.161.301111 (<a href="http://www.taoglas.com/images/product_images/original_images/AA.161.301111.pdf">http://www.taoglas.com/images/product_images/original_images/AA.161.301111.pdf</a>)<o:p></o:p></p><p class="MsoNormal">Antenna is on a 18” x 18” steel plate<o:p></o:p></p><p class="MsoNormal">Connected via FTDI->USB to Rasperry Pi<o:p></o:p></p><p class="MsoNormal">Raspberry Pi runs str2str to send the data to Windows laptop running rtknavi using wifi backhaul<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">The Rover setup is on a small mobile robot with a top speed of about 3mph. It is in a city (Pittsburgh), but the sky is relatively unobstructed.<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">I’m running rtknavi in Kinematic mode using only GPS, L1+L2, 15deg elevation mask. The position that I input for the base station is a 5 hour average (though it seems to have lost some precision when I pasted it?). I have tried both Continuous and Fix and Hold Integer Ambiguity Res. I’ll try to attach screen shots of rtknavi.<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">Right now, it kind of works. I can get relatively jitter-free floats and occasionally fixes, but these fixes don’t last long and I’m not sure they are actually globally accurate (ie: if you restart the software, you may get a fix, but it may be several meters from your last fix). Sometimes a fix goes away and never seems to come back.<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">I’m wondering if you guys have any suggestions to improve these results.<o:p></o:p></p><p class="MsoNormal">Better antennas? (Which ones?)<o:p></o:p></p><p class="MsoNormal">Trying to get better placement of the base station?<o:p></o:p></p><p class="MsoNormal">Different settings in rtknavi?<o:p></o:p></p><p class="MsoNormal">Continuous vs Fix and Hold?<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal">Thanks!<o:p></o:p></p><p class="MsoNormal">-Sean<o:p></o:p></p><p class="MsoNormal"><o:p> </o:p></p><p class="MsoNormal"><image001.png> <image002.png> <image003.png> <image004.png><o:p></o:p></p></div></div></blockquote><blockquote type="cite"><div><span>_______________________________________________</span><br><span>This message is sent to you from <a href="mailto:FOSS-GPS@lists.osgeo.org">FOSS-GPS@lists.osgeo.org</a> mailing list.</span><br><span>Visit <a href="http://lists.osgeo.org/mailman/listinfo/foss-gps">http://lists.osgeo.org/mailman/listinfo/foss-gps</a> to manage your subscription</span><br><span>For more information, check <a href="http://wiki.osgeo.org/wiki/FOSS-GPS">http://wiki.osgeo.org/wiki/FOSS-GPS</a></span></div></blockquote></body></html>