Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

GPS receiver frequency in acquisition stage

Status
Not open for further replies.

Wild Life

Member level 1
Joined
May 4, 2011
Messages
34
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Activity points
1,565
Hello everybody, I'm designing a GPS receiver, I'd only need an information:

I found an example of the Parallel Code Phase Search as the one here:

http://img339.imageshack.us/img339/5725/pcps.png

So, I understood everythingm, the only one thing is:

If I have a sampled signal as input, I have these samples with f frequency to be at first Fast Fourrier Transformed, then multiplied with a code and then the FFT should be inverted.

If I know I have to both FFT and IFFT with 2048 points, the output signal at the end of the module (the one is showed in the image), has frequency f/(2048*2048)?

Because if I've got an FFT signal for 2048 points I think the rate should be divided by 2048 and then, same thing for IFFT... or am i wrong?

---------- Post added at 16:14 ---------- Previous post was at 16:12 ----------

I forgot, in the image there's written Fourier Transform but, for faster and easier design, I have to use Fast Fourrier Transform and Inverse Fast Fourrier Transform (FFT and IFFT)
 

leeguoxian

Member level 3
Joined
Jun 20, 2006
Messages
66
Helped
6
Reputation
12
Reaction score
2
Trophy points
1,288
Activity points
1,778
I don't think I get your information correctly, but here is what I think :
The frequency for FFT calculation can be totally different with the sample frequency as long as you
registered all the gps data. Cause usually FFT take several iterations to finish, you can not run it during
reading gps data. So you will need to save the gps data into memory and read them out for FFT , and
then you can run FFT as fast as you want if your hardware design allows.
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top