1<?xml version="1.0" encoding="ISO-8859-1"?> 2<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"> 3<!-- 4This file is Copyright (c) 2018 by the GPSD project 5SPDX-License-Identifier: BSD-2-clause 6--><refentry id="gpsrinex.1"> 7 <refentryinfo> 8 <date>09 Nov 2018</date> 9 </refentryinfo> 10 <refmeta> 11 <refentrytitle>gpsrinex</refentrytitle> 12 <manvolnum>1</manvolnum> 13 <refmiscinfo class="source">The GPSD Project</refmiscinfo> 14 <refmiscinfo class="manual">GPSD Documentation</refmiscinfo> 15 </refmeta> 16 <refnamediv id="name"> 17 <refname>gpsrinex</refname> 18 <refpurpose>Read data from gpsd convert to RINEX3 and save to a file.</refpurpose> 19 </refnamediv> 20 <refsynopsisdiv id="synopsis"> 21 <cmdsynopsis> 22 <command>gpsrinex</command> 23 <arg choice="opt">-D <replaceable>debuglevel</replaceable></arg> 24 <arg choice="opt">-f <replaceable>filename</replaceable></arg> 25 <arg choice="opt">-h</arg> 26 <arg choice="opt">-i <replaceable>interval</replaceable></arg> 27 <arg choice="opt">-n <replaceable>count</replaceable></arg> 28 <arg choice="opt">-V</arg> 29 <group> 30 <replaceable>server</replaceable> 31 <group> 32 <replaceable>:port</replaceable> 33 <group> 34 <replaceable>:device</replaceable> 35 </group> 36 </group> 37 </group> 38 </cmdsynopsis> 39 </refsynopsisdiv> 40 <refsect1 id="description"> 41 <title>DESCRIPTION</title> 42 <para> 43 <application>gpsrinex</application> is a tool to connect to 44<application>gpsd</application> and output the received raw measurements 45as a RINEX 3 observation file. This is useful for sending raw measurements 46(pseudorange and carrierphase) from <application>gpsd</application> to 47a Precise Point Positioning (PPP) program or service.</para> 48 <para> 49 <application>gpsrinex</application> does not require root 50privileges, and can be run concurrently with other tools connecting 51to a local or remote <application>gpsd</application> without causing 52problems.</para> 53 <para>gpsrinex needs the GPS receiver to be sending raw measurements 54to <application>gpsd</application>. Only a few GPS have this capability. 55In addition, the <application>gpsd</application> driver for that GPS 56must support raw mode. Currently only the u-blox driver has this support. 57Only a few u-blox 8 GPS implment the required UBX-RXM-RAWX message. The 58NEO-M8T is known to work, but requires configuration with 59<application>ubxtool</application>.</para> 60 <para>RINEX has its own definitions and abbreviations. Be 61sure to consult their documentation. An observation file (.obs) 62contains data sets, called epochs, that contain the pseudorange 63and carrierphase for each satellite seen.</para> 64 <para> 65 <application>gpsrinex</application> by default will acquire 6620 epochs spaced apart by 30 seconds. That will take 10 minutes to 67complete. Most users consider the 30 second interval to be optimal. 68Many PPP programs require at least 1 or 2 hours data, but no more than 6924 or 48 hours of data. Most users consider 4 to 6 hours of data 70as a minimum for good accuracy. Additional hours will not yield much 71improvement. </para> 72 <para>The output will consist of one RINEX 3 observation file that 73is ready to be read by your PPP program. The default filename will be 74in the form: gpsrinexYYYYJJJHHMMSS.obs. You can override this filename 75with the -f option.</para> 76 <para>Optionally a server, TCP/IP port number and remote device can 77be given. If omitted, <application>gpsrinex</application> connects to 78localhost on the default port (2947) and watches all devices opened by 79<application>gpsd</application>.</para> 80 </refsect1> 81 <refsect1 id="options"> 82 <title>OPTIONS</title> 83 <para>-D [debuglevel] set debug level to [debuglevel].</para> 84 <para>-f [filename] save RINEX into [filename].</para> 85 <para>-h makes <application>gpsrinex</application> print 86a usage message and exit.</para> 87 <para>-i [interval] wait [interval] seconds between epochs. OPUS 88accepts intervals of 1, 2, 3, 5, 10, 15 or,30 seconds. OPUS then 89reduces the data to 30 second intervals. Defeault is 30.</para> 90 <para>-n [count] causes [count] epochs to be output. OPUS requires a 91minimum af 15 minutes, and a maximum of 48 hours, of data.</para> 92 <para>-V makes <application>gpsrinex</application> print 93its version and exit.</para> 94 </refsect1> 95 <refsect1 id="exampletitle"> 96 <title>EXAMPLES</title> 97 <para>Example 1:</para> 98 <para>Create a 4 hour .obs file. With a running 99<application>gpsd</application> accessible on the localhost do all of 100the following, in order. Order matters.</para> 101 <para>The raw measurement messages are long. Be sure your serial port 102speed is high enough: 103<programlisting> 104gpsctl -s 115200 105</programlisting></para> 106 <para>Disable all NMEA messages, and enable binary messages: 107<programlisting> 108ubxtool -d NMEA 109ubxtool -e BINARY 110</programlisting></para> 111 <para>The NEO-M8N will only reliably output raw measurements 112when only the GPS and QZSS constellations are enabled. If your PPP 113service can use GLONASS, then enable that as well. Be sure to 114disable, before enable, so as not to momentarily have too many 115constellations selected. 116<application>ubxtool</application>, as recommended by u-blox, enables 117the QZSS constellation in tandem with GPS. Disable all constellations, 118except GPS (and QZSS): 119 120<programlisting> 121ubxtool -d BEIDOU 122ubxtool -d GALILEO 123ubxtool -d GLONASS 124ubxtool -d SBAS 125ubxtool -e GPS 126</programlisting></para> 127 <para>Verify the constellations enabled: 128<programlisting> 129ubxtool -p CFG-GNSS 130</programlisting></para> 131 <para>Enable the good stuff, the raw measurement messages: 132<programlisting> 133ubxtool -e RAWX 134</programlisting></para> 135 <para>Verify raw data messages are being sent: 136<programlisting> 137ubxtool | fgrep RAWX 138</programlisting> 139You should see this output: 140<programlisting> 141UBX-RXM-RAWX: 142UBX-RXM-RAWX: 143</programlisting></para> 144 <para>Collect 4 hours of samples at 30 second intervals, save the 145RINEX 3 observations in the file today.obs: 146<programlisting> 147gpsrinex -i 30 -n 480 -f today.obs 148</programlisting></para> 149 <para>Wait 4 hours. Enjoy a meal, or do some exercise. When 150<application>gpsrinex</application> finishes, upload the file today.obs 151to your favorite PPP service.</para> 152 <para>Example 2:</para> 153 <para>Collect raw masurement data from a remote gpsd. The 154process it later with <application>gpsrinex</application> and 155<application>gpsprof</application>.</para> 156 <para>Ensure the GPS is configured properly, as shown in Example 1.</para> 157 <para>Grab 4 hours of raw live data from remote 158<application>gpsd</application> at 10.168.1.2: 159<programlisting> 160gpspipe -x 14400 -R 10.168.1.2 > 4h-raw.ubx 161</programlisting></para> 162 <para>When <application>gpspipe</application> is complete, feed the 163data to <application>gpsfake</application>: 164<programlisting> 165gpsfake -1 -P 3000 4h-raw.ubx 166</programlisting></para> 167 <para>In another window, feed the data to 168<application>gpsrinex</application>. Use -n 10000000 so that 169all the data from the raw file is used:: 170<programlisting> 171gpsrinex -i 30 -n 1000000 172</programlisting></para> 173 <para>Repeat the process with 174<application>gpsfake</application> to send the data to 175<application>gpsprof</application>.</para> 176 </refsect1> 177 <refsect1 id="see_also"> 178 <title>SEE ALSO</title> 179 <para>One service known to work with obsrinex output is at: 180https://webapp.geod.nrcan.gc.ca/geod/tools-outils/ppp.php</para> 181 <para>OPUS requires 2 frequency observation files. 182https://www.ngs.noaa.gov/OPUS/</para> 183 <para>The curious can find the RINEX 3.03 format described here: 184ftp://igs.org/pub/data/format/rinex303_update1.pdf</para> 185 <para> 186 <citerefentry> 187 <refentrytitle>gpsd</refentrytitle> 188 <manvolnum>8</manvolnum> 189 </citerefentry>, 190<citerefentry><refentrytitle>gpsfake</refentrytitle><manvolnum>1</manvolnum></citerefentry>, 191<citerefentry><refentrytitle>ubxtool</refentrytitle><manvolnum>1</manvolnum></citerefentry>. 192</para> 193 </refsect1> 194 <refsect1 id="maintainer"> 195 <title>AUTHOR</title> 196 <para>Gary E. Miller <email>gem@rellim.com</email>.</para> 197 </refsect1> 198</refentry> 199