[teqc] Converting Android GPS data to Rinex file format

Lalitha myracacc at gmail.com
Wed Oct 13 15:58:02 MDT 2010


* <http://ls.unavco.org/mailman/listinfo/gpstech>*I could see the mailing
lists 'GPS Tech Discussions' and 'tecqc support' that seemed to be relevant
to this topic. And i addressed to both the mailing lists.
I couldn't find GPSS in the unavco support page!

correct me if I've to use some other mailing list so that i can use next
time the right one.

Thanks,
Lalitha.

On Wed, Oct 13, 2010 at 2:51 PM, James Johnson <jjohnson at ucar.edu> wrote:

> Oh, didn't think about it, just responded....  Next time.  I guess I should
> subscribe from GPSS.
>
> Jim
>
> On Oct 13, 2010, at 2:54 PM, rocken wrote:
>
> > Why not use you gpss email for this?
> > Lots of visibility.
> >
> >
> > On Oct 13, 2010, at 11:44 AM, James Johnson wrote:
> >
> >> Hi Lalitha,
> >>
> >> It is not possible to generate RINEX from an android phone.  This is
> because the raw data required for RINEX is not exposed by the Android API.
>  You can get some information about the SVs tracked and a position, but you
> can not get the raw Pseudo range data.  The NMEA strings are not useful for
> generating RINEX as well, simply because the data is not there.
> >>
> >> Sorry for the sad news.
> >>
> >> Best Regards,
> >> Jim Johnson
> >> On Oct 13, 2010, at 11:40 AM, Lalitha wrote:
> >>
> >>> Hi Homan,
> >>>
> >>> Tons of thanks for the detailed reply. I've been searching the net and
> posting in all the android, gps forums for the past 10 days and didn't get
> any response till now. Thanks to teqc mailing list.
> >>>
> >>> Q1. I checked the android api for the gps data. It provides GPS
> Satellite info from which we can get elevation, PRN (pseudo-random number),
> snr, Almanac, ephemeris data etc.
> >>>    Ref :
> http://developer.android.com/reference/android/location/GpsStatus.html
> >>> With these data, will it be possible to generate Rinex file directly
> from android app?.
> >>>
> >>> Q2. Also, there is a nmealistener provided in the android api using
> which we can capture gps nmea strings. Will this data be useful by anyway to
> translate to rinex format? (Though, I coudnt succeed capturing nmea string
> using my htc magic phone, I can try with some other phones if this data will
> be  useful for post processing).
> >>>
> >>> Thanks,
> >>> Lalitha.
> >>>
> >>> On Wed, Oct 13, 2010 at 9:58 AM, Homan, Thomas <thoman at co.gila.az.us>
> wrote:
> >>> Lalitha,
> >>>
> >>>
> >>> .gpx files cannot be converted to Rinex as they don’t contain the
> necessary data elements. If I remember correctly, the api only outputs the
> final latitude and longitude values. I don’t believe the underlying raw gps
> data is accessible but I’m just getting started on Exclipse.
> >>>
> >>>
> >>> To generate a Rinex file you need to have access to underlying
> information such as pseudorange, carrier phase and other data from each
> satellite in the GPS constellation. As an example, below are a .gpx file
> compared to a Rinex file that I collected in 2005. Each of the 7 satellites
> visible has a set of 7 data elements logged out of my $$$ survey grade
> receiver and this happens each logging period.
> >>>
> >>>
> >>> Peruse the api docs and see if there is access to the underlying data
> and not the final coordinates. If not, then you might be out of luck. One
> thing you might explore is if the android OS supports inserting DGPS
> correctors so you could get real time sub-meter accuracies.
> >>>
> >>>
> >>> Hope this helps some.
> >>>
> >>>
> >>> Tom
> >>>
> >>>
> >>> GPX
> >>>
> >>> <?xml version="1.0" encoding="ISO-8859-1"?>
> >>>
> >>> <gpx xmlns="http://www.topografix.com/GPX/1/1" xmlns:xsi="
> http://www.w3.org/2001/XMLSchema-instance" version="1.1" creator="Doug
> Forster's map viewer" xsi:schemaLocation="
> http://www.topografix.com/GPX/1/1
> http://www.topografix.com/GPX/1/1/gpx.xsd">
> >>>
> >>> <wpt lat="-42.48781" lon="172.29404">
> >>>
> >>> <ele>1273</ele>
> >>>
> >>> <name>NwDvls</name>
> >>>
> >>> <cmt> 30/01/10 19:14</cmt>
> >>>
> >>> <desc>New Devils Den Biv</desc>
> >>>
> >>> <sym>Anchor</sym>
> >>>
> >>> <extensions>
> >>>
> >>> <type xmlns="Freshmap">Place</type>
> >>>
> >>> <TrackColor xmlns="Freshmap">0</TrackColor>
> >>>
> >>> <FontSize xmlns="Freshmap">90</FontSize>
> >>>
> >>> <GPSColor xmlns="Freshmap">14</GPSColor>
> >>>
> >>> <Layout xmlns="Freshmap">5</Layout>
> >>>
> >>> </extensions>
> >>>
> >>> </wpt>
> >>>
> >>> </gpx>
> >>>
> >>>
> >>> Rinex
> >>>
> >>> 05 10 12 14 44 45.0000000  0  7G 1G24G23G20G16G25G11
> >>>
> >>> 18540407.76711  14441990.35651  22140106.912    22140108.9425
> 22140103.6715
> >>>
> >>>    -1502.342       -1170.656
> >>>
> >>> 18405511.80411  14342294.04151  23619878.513    23619880.7005
> 23619875.3565
> >>>
> >>>      382.895         298.360
> >>>
> >>> 18279304.44211  14260112.94351  22317896.240    22317897.3485
> 22317888.9405
> >>>
> >>>     2122.449        1653.856
> >>>
> >>> 18331079.75811  14289623.90551  20672596.529    20672597.6675
> 20672590.3895
> >>>
> >>>     1386.704        1080.549
> >>>
> >>> 18282886.39611  14256935.72751  21779940.978    21779941.1535
> 21779934.4995
> >>>
> >>>     2177.108        1696.448
> >>>
> >>> 18595837.79911  14470056.42251  21824971.770    21824972.4395
> 21824966.6485
> >>>
> >>>    -2263.324       -1763.629
> >>>
> >>> 18612482.40511  14492926.57751  23828871.571    23828874.4325
> 23828869.0685
> >>>
> >>>    -2470.753       -1925.262
> >>>
> >>>
> >>> From: teqc-bounces at ls.unavco.org [mailto:teqc-bounces at ls.unavco.org]
> On Behalf Of Lalitha
> >>> Sent: Wednesday, October 13, 2010 9:03 AM
> >>> To: teqc at ls.unavco.org; gpstech at ls.unavco.org
> >>> Subject: [teqc] Converting Android GPS data to Rinex file format
> >>>
> >>>
> >>> Hi,
> >>>
> >>> How do i convert the gps data I get from Android GPS Receiver into
> Rinex file format in order to do Post processing corrections.
> >>> I can write the gps data into .gpx format using the android api
> provided. I use HTC Magic phone with 2.2 api version.
> >>> I cudnt find option for android in the teqc toolkit. Can anyone help
> how do I convert to Rinex?
> >>> Also I'm looking for the post processing softwares or service available
> for evaluation. I could find only one free evaluation software 'PPro2' from
> Kinematic GPS.
> >>> Is there any other free post processing software present?
> >>>
> >>> Thanks,
> >>> Lalitha.
> >>>
> >>>
> >>> _______________________________________________
> >>> teqc mailing list
> >>> teqc at ls.unavco.org
> >>> http://ls.unavco.org/mailman/listinfo/teqc
> >>>
> >>>
> >>> _______________________________________________
> >>> teqc mailing list
> >>> teqc at ls.unavco.org
> >>> http://ls.unavco.org/mailman/listinfo/teqc
> >> _______________________________________________
> >> teqc mailing list
> >> teqc at ls.unavco.org
> >> http://ls.unavco.org/mailman/listinfo/teqc
> > _______________________________________________
> > teqc mailing list
> > teqc at ls.unavco.org
> > http://ls.unavco.org/mailman/listinfo/teqc
> _______________________________________________
> teqc mailing list
> teqc at ls.unavco.org
> http://ls.unavco.org/mailman/listinfo/teqc
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://ls.unavco.org/pipermail/teqc/attachments/20101013/17c8227b/attachment.html


More information about the teqc mailing list