Some links but also questions about AGPS ;) Re: Power of A-GPS

[Robert Michel]

Salve Robert!

Robert Michel schrieb am Samstag, den 11. November 2006 um 19:46h:
> And A-GPS can serve local coordinates even inside of buildings
> or in other situations that no or not enough GPS satellites
> could be used:
> http://en.wikipedia.org/wiki/A-GPS

It seems that the wikipedia article is not good enough
and it needs some more information to underastand assisted GPS.
(Or I have the need for some more information - and I think other
people are interested in learning more about AGPS as well ;)
So when we want to support the OpenMoko/Neo1973 project and
want to hack it well - charing good tutorials/documentations 
could help us)

Sean put the information "Global Locate AGPS chip" on the webpage,
that helps to find some more information:
http://www.globallocate.com/
To reduce size and cost *speculating* the Neo1973 could have
a single apgs chip hammerhead....
http://www.globallocate.com/SEMICONDUCTORS/HAMMERHEAD_PB.pdf
http://www.globallocate.com/SEMICONDUCTORS/SEMI_LIBRARY_Frameset.htm

Ah - maybe this presentation is a good starting point:
http://www.freescale.com/files/ftf_2006/doc/presentations/Americas/AM107.pdf

Just connected via serial host interface (UART,SPI or PC), but
"both A-GPS control software and LBS (location based services)
application executed on host CPU of cellular processor."
That sounds that this part won't be open and runs as binary.

About this software:
http://www.globallocate.com/SEMICONDUCTORS/SEMI_DRIVER_Frameset.htm
"All elements needed by JSR179 interface supported by C API."

Most of you will probably say hey JSR-179
http://jcp.org/jsr/detail/179.jsp
that's fine - you don't have to care about AGPS and how it works.

http://www.linuxdevices.com/news/NS6857451192.html
"MR2 [MilestoneRelease2] of phoneME Feature, due by year'sh ens, with participation 
from the community, will add "full-stack multitasking safety," and
increased portability, as well as full or partial implementations of JSR
APIs that include:

* Personal Information and File Management (JSR 75)
* Bluetooth and OBEX (JSR 82)
* Wireless Messaging API (JSR 120)
* Mobile Media API (JSR 135)
* J2ME Web Services support (JSR 172)
* Security and Trust Services API support (JSR 177)
* Location API for J2ME (JSR 179)
* SIP API for J2ME (JSR 180)
* Java Technology for the Wireless Industry (JSR 185)
* Wireless Messaging API 2.0 (JSR 205)
* Content Handler API (JSR 211)
* Scalable 2D Vector Graphics (JSR 226)
* Payment API (JSR 229)
* Mobile Internationalization API (JSR 238)
* Java Binding for the OpenGL(R) ES API (JSR 239)
more: https://phoneme.dev.java.net/  


Well, I study civil engineering so I'm interested in detail how it
works, but also as a (low level) hacker/developer I'm interested in
costs and data privatcy:

Because AGPS needs data "assistance data" work indoor, the questions are
- where to get this data from
- need this GPRS connection (traffic costs)
- does this data access is free (beside traffic costs)
- does my networkprovider or another company get informations
of my localisation requests?

If yes: is there a chance that I/we can run GPS basestations
for creating "assistance data" ourself? Would this be compatible
with the "Global Locate" binaries?
Are there already free server for GPS data?


I haven't played with GPS and Linux (yet!!), but this looks
very interesting:
http://www.gpsdrive.cc/
This software does already have a friendsd:
   "There is a server program, called friendsd which acts as server for
    theposition of your friends. If you enable it in the settings menu, 
    then you can see the position of all gpsdrive connected with this 
    server."

BTW to compare AGPS with other indoor navigation techniques:
Ph.D work of Holger Linde, August 2006:
"On Aspects of Indoor Localisation"
http://eldorado.uni-dortmund.de:8080/bitstream/2003/22854/1/dissertation_linde.pdf 


Hope that someone of you can add some informations ;)
Greetings,
rob



PS: I guess AGPS will redraw the need for external antennae, in normal
live, but away of the range of GSM (ship, jugle, antartica..) it could be still
interesting... examples for self-building:
http://www.ggrweb.com/article/gulley.html
http://home.iae.nl/users/plundahl/antenne/helical.htm
http://www.radio-active.net.au/web/gps/pipe.html
*g*