Friday, April 6, 2007

The SiGe GN3S signal spectrum (bought @ sparkfun.com)

Fig 1: The SiGe GN3S sampler signal spectrum

6 comments:

Jeffer said...

Hi Michele:
I am a research person in Hong Kong Polytechnic University. I am very interested in the GPS Software Receiver as well. I see your comment in the SiGe GN3S Sampler's order website. The 600 MB limitation is still a problem to me. You konw, the 600 MB is not enough for many GPS Software Receiver research areas. So I want to consult you kindly: can you resolve this problems?
dbqr@163.com This is my email, you can just email me or contact with the msn (my msn: mjfdbqr@msn.com).
I am looking forward your email back, and I hope we can be a friends. Many thanks to you !


Jeffer

w said...

Hello Michele and Jeffer,

I recently acquired the SiGe front-end module to accompany the SDR GPS and Galileo book.

I've taken a few samples, but when I load the data into the software developed by the book's authors, it does not locate any GPS satellites.

I know this could result from many different things, but I was wondering if either of you had difficulty getting it to work correctly at first.

Any suggestions?

Thanks,
Bill

(form51@gmail.com)

Michele Bavaro said...

Bill,
I'm sorry for such along wait, but I'm not checking this Blog since a lot of time. Actually no, I didn't have many problems in receiving GPS satellites...
I'm sure you changed the reference sampling and intermediate frequency...

The next time please, contact me at my e-mail address (michele.bavaro@) so that I will be able to reply immediately :)

Ciao,
Michele

Mauro said...

Hello,

We have been experiencing a probable malfunctioning of the SiGe GN3S Sampler v2: data seem properly acquired (no SW errors), but no satellite acquisition has been ever performed by using our SiGe Sampler.

Last month (sep 11) we have purchased a SiGe GN3S Sampler v2 from Sparkfun together with the antenna advertised on the same page.

We have been using the matlab code from "A software-defined GPS and Galileo Receiver- A single frequency approach" (Kai Borre) both on a Windows 7 and Windows XP machine

For SiGe version 2 we replaced the .m files contained in the SDR with the updated ones downloaded by the GNSS web site of Colorado University for the processing of the I/Q data and we used the parameters indicated on the same web site : (in order to validate this SW, we have also generated a proper sample IQ file and the SDR properly acquired the GPS satellites we had coded into the IQ file).

Sampling frequency : 8.1838 MHz
Intermediate frequency : 38.400 KHz

Again, all the software runs smooth but no satellites have ever been acquired in a clear sky view (i.e. no trees, no buildings, at Rome-Italy latitude) and the University of Colorado still did not provide any hint to solve the problem.

Could you provide any troubleshooting support?

Michele Bavaro said...

Hi Mauro,

I don't support the SiGe GN3S.

Nevertheless, you didn't provide enough information. For example, did you test the acquisition software with another file (known to work) to rule out a simple configuration problem?

Could you also post a snapshot of the file you are testing or at the very least the spectrum and the histogram of the digital samples?

Best wishes,
Michele

P.S.: Might be easier to continue this conversation via e-mail.

Mauro said...

Hi Michele,

Thanks for your reply. My email is fulci83@hotmail.it.
Send me an email to keep in touch and continue the conversation.

Regards,

Mauro