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GNSS Internet Radio and Built in GPS

Hello,
I am new to the forum and also the owner of an HTC Fuze. I have been playing around recently with the GPS on the phone and got me thinking. I live in NY and we have a CORS network of gps base stations that are fed by the use of ntrip.
I was wondering if their was any way to use the gps signal on my phone and the connection to this CORS network to give me sub inch accuracy on my phone...then not sure what I would do with it then. But I do live on a farm and I would like to see some type of precision agricultural use.
I guess I need a way to have the GPS on the phone talk with the GNSS internet radio and then give me spot on guidance and such.
Please let me know your thoughts or if I need to explain better.
Thanks,
Clayton

bump
bump. Any ideas? Anyone

Great idea cwrisrey !
That will save the cost of a geodetic device, which is many times the cost of a Fuze. Further, it will lead the accuracy of the buildin GPS into millimum class.
Not dig into this further, would you go further to tell these:
Is that CORS data encrypted?
Is that accessible through public internet or VPN?
Is there copy right or intellectuall property right issue involved? (I don't think so, but better make it clear first)
Once again, great idea. Please do remember to update this thread once you got any progress. Thanks.

More info
Hello wg5566,
This site would probably answer alot of your questions clearer than I could:
http://www6.nysdot.gov/spiderweb/frmIndex.aspx
* Is that CORS data encrypted?
-I don't believe so, I think that it is just a form of compression, to distribute across the internet.
* Is that accessible through public internet or VPN?
Yes, the NYS CORS anyway. It accessible from the public internet (although they require you to register with them) But I believe there are other free streams. I also believe it was modeled after being able to be sent threw GPRS.
* Is there copy right or intellectuall property right issue involved? (I don't think so, but better make it clear first)
-I believe the ntrip is based on a GNU, I think the source code is available. http://igs.bkg.bund.de/index_ntrip_down.htm
Windows CE version:
http://www.ilmb.gov.bc.ca/crgb/gsr/downloads/installGNSS.CAB
Please, let me know your thoughts...
Thanks,
Clayton

My fast thoughts:
First make sure there is no satisfied freeware currently available for WM.
If so please ask a moderator to move this to the development & hackings section. And Add tyis sentence on the title: Call for developers for revolutionary GPS app!
I'm sure somebody here can develop this. You know the geodetic device was invented many years ago with very weak profiles comparing to current WM devices. The hardware on our phone should be capable to deal with these calculations, and the WM Pro platform should be capable to support such an app. Anyway it should not be a biggy for many masters here. But it is a biggy for gps users with high accuracy demand for any reason.
Edit: Did you try install that wince cab on your phone? I think some of WINCE apps can just run on WM. Please backup your data first.
Edit2: I tried to install it on my device, at first it did not show up in start menu, then I found the cab just put files and shortcut in the folder names in French. But there is no registry involved in the cab. Only three files. And then program UI itself is in English. Just run the executable from the folder will go right out of the box. So please try it. I did not try to connect & loggin yet, due to not registered account.
Edit3: Looks like the cab is only access the data from internet, convert the data format and export the data, but we still need a geodetic/gps software to process/use the data.
Disclaimer: I attatched these three files for the only purppose of exchanging software developement infomation. Anybody if download it please do not use it for any purppose other than this. Thanx.

Some thoughts on the subject
Hi All,
The idea of using NTRIP to make a Windows Mobile GPS device sub-meter accurate crossed my mind. After some research I found this thread.
Unfortunately, I haven't been able to find any software capable of doing this. My idea is that it should be possible to accomplish this goal, using a combination of existing tools (which would be really cool!).
As wg5566 notes, there is a (WM) tool called GNSS Internet Radio, which is capable of downloading NTRIP corrections. It turns out this software works, but does have some flaws. Someone wrote another open source tool which is better (?), but unfortunately it isn't built for Windows Mobile (see: http://lefebure.com/software/).
More searching revealed a (dead?) project on codeplex: SharpGPS. It's an unfinished demo. It does however seem to be designed to do exactly what we're suggesting in this thread.
My idea: Completing the WM version of SharpGPS with parts of GNSS Internet radio / lefebure NTRIP client should result in a tool that's capable of upgrading a WM devices' gps signal to sub-meter accuracy through RTK/DGPS corrections over NTRIP.
Any ideas / suggestions about this?

It's already been done for the commercial market
Land surveyors, construction companies, and farmers use RTK GPS and RTK GNSS correction services on a regular basis. Some are free and some are paid subscription. They can be either NTRIP protocol with casters or individual TCP or UDP connections. Examples of software available are Carlson SurvCE and MicroSurvey. Read Carlson's support site for how they deal with the data flow using such networks on SurvCE (Windows Mobile and CE).
I have worked in land surveying using such equipment, and it generally requires dual frequency receivers, RTK corrections, and high quality antennas to achieve 1-2cm 95% CI horizontal precision. The current GPS chips in cell phones are only single frequency and so the best you could expect under ideal conditions is 2'-3' precision using some form of differential correction like WAAS or beacon or DGPS via NTRIP. Under average conditions, the precision will likely be in the 10-20' range. The dual frequency receivers take care of the large errors caused by radio waves traveling through the ionosphere.
Due to the limitations of batteries, antennas, and space for more chips in cellphones, the future of location accuracy will likely include some combination of GPS/GLONASS and cellular radio signal frequency timing calculations from cell towers. True Position, with its U-TDOA technology, is one example of measuring the time differences of cell phone radio waves using cell towers with known coordinates. Rumors (from surveying journals) have it that there are current patents in place that can allow for sub foot precision using such methods when sufficient cell towers are present for multilateration.

Has anyone found success on this topic? WM or Android...

Would be very interested, since there is a free NTRIP feed available in Switzerland... anyone?

*bump* it up

Been there still trying. Problem is no carrier phase off internal gps.

Grimli said:
Hi All,
The idea of using NTRIP to make a Windows Mobile GPS device sub-meter accurate crossed my mind. After some research I found this thread.
As wg5566 notes, there is a (WM) tool called GNSS Internet Radio, which is capable of downloading NTRIP corrections. It turns out this software works, but does have some flaws. Someone wrote another open source tool which is better (?), but unfortunately it isn't built for Windows Mobile (see: /lefebure.com/software/).
Click to expand...
Click to collapse
Lance lefebure is a really cool guy I'm sure he wouldn't have any problem building a wm version but it is going to takea lot more than that to get rtk to a cell phone.

Very good ,thanks.

Ed hardy bikini said:
Very good ,thanks.
Click to expand...
Click to collapse
If you are confused just ask questions and I will do my best to answer them. I am in the ag industry and deal with RTK networks and different ways of connecting them and tons of different gps units on a daily basis.

Look at this:
http://stakemill.wordpress.com/2010/07/19/ashtech-mobile-mapper-100-supports-esri-arcpad-10-0/
and this:
http://www.ashtech.com/-2359.kjsp?RH=1272644205746&RF=1270806507068
Is that still a phone !?

wg5566 said:
Look at this:
Is that still a phone !?
Click to expand...
Click to collapse
Nope PDA with support for external GPS with a builtin reciever that even sees glonass satellites (russian constelation). That was made specifically to do RTK mapping. It does have a GSM radio for data to connect to the cors.

Phone positioning using CORS
To perform a CORS (Network Reference correction we need a GGA stream from the GPS in your device. This allows us to remove the anomalies and provde the correction stream. As phones use a sirf II chip or similar they do not have input capability to output the NMEA stream to achieve this.

This one works great! it will connect to an Rtk receiver and get the nmea string from it or will use the internal GPS to be able to register on the CORS network. It will then stream the corrections over Bluetooth to a receiver or even a repeater radio. It won't however correct the internal GPS. http://antrip.dyndns.biz/Home/DownloadTrial

[Q] What‘s the detail role of btdwake.exe

I want to know the specific functions of the btdwake.exe in the startup. Please give it out details. Thanks a lot.

OK. I found the answer through the search in the XDA.
btdwake = Bluetooth Disk Driver (BT FTP)

[Q] GFMAPI Project - FM Radio RSSI to dB?

Hi everyone,
I'm working on a project that uses the GFMAPI library that allows a developer to make use of the FM radio capabilities of a phone. I have an HTC Touch Diamond phone running Windows Mobile 6, and everything is working fine. I can get a measure of RSSI (received signal strength indicator) for any given radio station.
According to the Wikipedia article for RSSI, there is no standard definition of how to convert an arbitrary RSSI value to decibels (dB). My question is, does anyone know of a way to do this? I tried looking for manufacturing specifications for my particular phone, but couldn't fine anything useful. Perhaps someone else has had this problem?
Thanks for any help you can offer.
-Mike

Understanding Android GPS Architecture

Plz see the Attached GPS Architecture diagram 1st before reading below Article:
Location Services using GPS in Android consist of following Architectural Components
1) GPS Chip
2) GPS Driver
3) GL Engine
4) Android Framework
5) User Applications
Now Lets Understand each
GPS Chip: Radio Frequency Receiver that directly communicates with GPS Satellites
GPS Driver: GPS Driver System Software that uses Low level API’s to Communicate with the GPS chip, at the system level it may consist of a single or multiple files located at /System/Lib/hw/ Or /Vendor/Lib/hw/ files names usually starts with Prefix GPS and Postfix So (i.e gps.default.so or gps.aries.so e.t.c) depending upon the Android version and Smartphone Platform.
GL Engine: Actually the heart of this overall system.
At System level it consist of files at Path /system/bin with names like glgps or gpsd (Platform Specific)
It works using the Configuration Parameters which consist of .xml and .conf files (i.e glconfig.xml, gps.xml, Jupiter.xml, gpsconfig.xml and gps.conf, secgps.conf e.t.c). The Physical Location and names of files again depends upon Android version and Platform, but they are mostly at (/system/etc , /system/etc/gps , /vendor/etc/, /data/gps e.t.c), depending upon the Configuration and Platform, it takes initial Location Information from Cell Towers, then it take it read NVRAM , it is most important as here it store assistance data from GPS Lock, and it may also use xtra data.
NVRAM information is mostly location at /data/gps in a file with .sto ext (i.e gldata.sto) and xtra data files (lto.dat, xtra.bin, epo.dat e.t.c Platform dependent),
Using all this information Gl Engine instruct / Assist the GPS Driver, mostly Gl Engine is able to Detect multiple GPS satellites for which it is GPS driver is Programmed, but to Lock it need some extra information (Timing, Alm. / Emp.e.t.c) which it could either download from GPS satellites (Standalone Mode: very slow speed bits/sec.) or it could use internet to access SUPL/NTP servers (MS Based/MS Assisted Fast speed MB/sec.)
After all this activity, it saves all the data in NVRAM for future use.
Android Location Services : It consist of Android Framework Classes like Location Manager that Provide services to the use applications using the GL Engine.
User Applications: Location services Applications like Google Maps, Sygic, Navigon , TomTom e.t.c.
Keeping all this information in mind now lets see how the GPS Faster Fix Solutions in Market do.
Faster Fix Solutions like GPS Status & Tool Box, GPS Test, GPS Doctor e.t.c mostly handle two things.
1) Download XTRA Data (lto.dat , xtra.bin , epo.dat, gldata.sto e.t.c)
2) Modify GPS.conf (Root Required)
But this not always works.
Devices uses Google as Supl Server but most devices are unable to use it due to invalid/expired certificates and Google servers rejects the Assistance requests in such scenario Users should use SUPL.NOKIA.COM:7275 , which although slow (but something is better then nothing)
If something is wrong with GL Engine or GPS Driver, it may need Re flashing but a little could be done if GPS Chip Reception is Low or Problem is at Hardware Level, some time need soldering skills for hardware alteration (Risky)
http://forum.xda-developers.com/showthread.php?t=1318892
The Other Configuration Parameter which users could modify is xml Configuration file( Take Backup 1st) at Least a Programmer could get Debug Log to understand where things are going wrong, using below parameters.
cLogEnabled="true" acLogDirectory="/sdcard/gps" and LogPriMask, LogFacMask and also DEBUG_LEVEL (gps.conf)
Hope everyone could easily improves their GPS Performance using this guide for any platform.

Wow, thank you, this is very useful!

Neat! Thanks!

hi
can you please explain the extensive location settings from google maps ... i searched google's help and i'm still confused.
for eg, what is the difference between "report from this device" and "enable location history"?
i guess they generate the trafic info using the data from our phones ... how?
thanx!
Happy Holidays! and Happy New Year!

jean2323 said:
hi
can you please explain the extensive location settings from google maps ... i searched google's help and i'm still confused.
for eg, what is the difference between "report from this device" and "enable location history"?
i guess they generate the trafic info using the data from our phones ... how?
thanx!
Happy Holidays! and Happy New Year!
Click to expand...
Click to collapse
'report from this device' is used in latitude. latitude allows you to share your location with your 'friends'. 'enable location history' is for you only and keeps a record of everywhere you go. or at least thats my understanding of it. hope this helps

Thanks for this "sort of" schematic! Keep on making some new schematics! :cyclops:

Dude i dint think ill tamper with gps in my life but the info you provided is just to simple and cool. thanks

mbbauk said:
Dude i dint think ill tamper with gps in my life but the info you provided is just to simple and cool. thanks
Click to expand...
Click to collapse
I agree. I've always enjoyed learning about gps starting from my Garmin iQue days. After suffering with the Captivate and that horrible gps it's nice to have a phone with fantastic gps and the ability to truly use it. Good stuff here!
Sent from my SG Note i317 via XDA Premium...I eat apples, not use them.

Hi
Speaking about GPS, is there any onchip limitation regarding the speed or location that it should grab GPS signal ?
Someone told me that it may not be possible to make it work in a plane because of US rules and security.. or around some sensitive FBI or Governments buildings (that may have signal killers) ?
Thanks

ak074 said:
'report from this device' is used in latitude. latitude allows you to share your location with your 'friends'. 'enable location history' is for you only and keeps a record of everywhere you go. or at least thats my understanding of it. hope this helps
Click to expand...
Click to collapse
first ... with both disabled ... maps and search still search your location .. which is strange ...
second ... if i enable location history, but not report from the device ... there is no history ! or i don't know where to find it ... cause, indeed it's not in latitute ... you can select "report from the device" without selecting history ... not sure if anything happens ...
Happy New Year!

wow mind blowing and extensive work to understand all this about global positioning system ...

Simple question to OP
Can the Broadcom chipset XTRA file- lto2.dat be used for Qualcomm chipset XTRA file - xtra.bin ? and vice versa?

Thank you.

popcorn1122 said:
Simple question to OP
Can the Broadcom chipset XTRA file- lto2.dat be used for Qualcomm chipset XTRA file - xtra.bin ? and vice versa?
Click to expand...
Click to collapse
To My Understanding and Experience "NO",
putting lto2.dat file in a Qualcomm Android Phone do not improve Time To First Fix (TTFF), did'nt experimented BroadCom.
also contents of both files seems different, MediaTek processors uses EPO files instead, but it is astonishing that lto2.dat do improve their TTFF.
But no technical document to prove these experimentation .

US past policy do restrict the use of GPS above certain altitude (to deny military use of GPS), but cell phones still acquire navigation using GlONASS in Planes.

Can anyone tell me which files are responsible for GPS? I used TitaniumBackup and I suspect that I deleted these files by mistake because now I do not receive a signal outside the building
Lollipop 5.0.1 GT-I9505

Help with dementia coffeemaker app.

Hi,
I am working on a coffeemaker that helps people diagnosed with dementia getting a bit of there independence back. It has to show the directions of the coffee making process. The coffeemaker has some sensors placed on it to register what steps have already been completed and has a arduino + bluetooth module for communication. I would like to build an app that makes it possible to show a particular page of the app>res>layout depending on what number it gets from the arduino. So basicly it should whent receives like a 4 from the arduino it should set the contentview to r.layout.4. I am a absolute noob at android programming and I have no clue where to start. I even cant get the Bluetooth connection to work. The arduino code is working so when I am using a android Bluetooth serial terminal I can communicate with the arduino.
So it has to fetch the data of the incoming bluetooth (serial) data and according to that data view a page on the app.
I am also able to create the layoutfiles with the desired text and pictures.
Do you guys have some tips and like a good tutorial for me or some help/advice?
I have looked at the android development pages but I simply cant get it to work.
Thank you in advance,
Marijnsp