[Openbts-discuss] Fwd: How RRLP 'MS assisted GPS' really works

[David A. B. <dbu...@jc...>]

FYI -

Interesting comments on RRLP and assisted GPS from the OpenBSC list.   
My apologies for the spam to those who are subscribed to both lists.

-- David


Begin forwarded message:

> From: "Dieter Spaar" <sp...@mi...>
> Date: December 12, 2010 5:42:12 PM PST
> To: "Harald Welte" <la...@gn...>
> Cc: Wolfgang Spraul <wol...@sh...>, Sylvain Munaut  
> <24...@gm...>, Holger Freyther <ze...@se...>, Daniel  
> Willmann <da...@to...>, Cristian Paul Peñaranda  
> Rojas <pa...@kr...>, op...@li...
> Subject: Re: How RRLP 'MS assisted GPS' really works
>
> Hello Harald,
>
> On Sun, 12 Dec 2010 17:01:22 +0100, "Harald Welte"  
> <la...@gn...> wrote:
>>
>> Pretty interesting.  If only I had the time to implement it ;)
>
> I don't think that implementing is the hard part, debugging is. You
> send data which might be wrong due to some bugs in your code into a
> "black-box" which does something with the data. The "black-box" will
> not tell you if your data are wrong, if they are, it might just take
> longer till any results are returned. So you are not sure if you are
> doing the things right.
>
> I conclude the above from my experience so far: Even phones with very
> extensive tracing capabilities don't tell you much about what is going
> on during their GPS position calculations. And at least I am not aware
> of a GPS server I have access to who will provide those data required
> for an "MS-assisted" measurement so that one could compare the own
> calculation against a reference.
>
> If someone know about a server providing those data (I am not
> talking of things like "almanac" or "ephemeris" here) or knows
> about existing source code to do the calculation, I would like
> to know.
>
> BTW, the book "Server-Side GPS and Assisted-GPS in Java" contains
> a few nice chapters, one should not care about "Java" in the title,
> only the examples are written in Java.
>
> Best regards,
>   Dieter
> -- 
> Dieter Spaar, Germany                            
> sp...@mi...


David A. Burgess
Kestrel Signal Processing, Inc.