discuss-gnuradio
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Discuss-gnuradio] Competition! Re: Discuss-gnuradio Digest, Vol 6, Iss


From: Jack Powers
Subject: [Discuss-gnuradio] Competition! Re: Discuss-gnuradio Digest, Vol 6, Issue 25
Date: Tue, 27 May 2003 09:54:18 -0700


On Tuesday, May 27, 2003, at 09:03 AM, address@hidden wrote:

Send Discuss-gnuradio mailing list submissions to
        address@hidden

To subscribe or unsubscribe via the World Wide Web, visit
        http://mail.gnu.org/mailman/listinfo/discuss-gnuradio
or, via email, send a message with subject or body 'help' to
        address@hidden

You can reach the person managing the list at
        address@hidden

When replying, please edit your Subject line so it is more specific
than "Re: Contents of Discuss-gnuradio digest..."


Today's Topics:

   1. USB2 <-> fast ADC & DAC (Andy Green)


----------------------------------------------------------------------

Date: Tue, 27 May 2003 15:58:50 +0100
From: Andy Green <address@hidden>
To: address@hidden
Subject: [Discuss-gnuradio] USB2 <-> fast ADC & DAC
Message-ID: <address@hidden>
Content-Type: Text/Plain;
  charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Precedence: list
Message: 1

=2D----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hi folks -

My friend Milosch and I are interested to make a generic USB2 <-> fast=20 ADC and DAC board, based around a Cypress FX2 chip, a FIFO and a fast=20
ADC and/or DAC.  We are both experienced engineers and expect no=20
difficulty with the digital side.

This is intended to be a completely generic USB-powered baseband=20
module with all processing done back at the PC in realtime.  Milosch=20
did some tests and found it was possible to transfer 20MBytes/sec=20
like this with latencies of under 2mS over USB2. It is this transfer=20
rate which is the limiting factor, not the conversion rates on the=20
ADC or DACs.

We have a use for this design already, but we are interested to see if=20 with some guidence from yourselves it can be made to be of use to the=20 gnu radio project too, since it will be cheap, small and selfpowered. =20
Some areas that we would welcome opinions on:

 - I assumed that a baseband-only device like this is in fact useful=20
for this project.  However I see existing designs are interested in=20
outputting modulated RF at ~30MHz via an FPGA or DSP.  Is a=20
baseband-only device even useful?

 - What resolution and speed ADC is needed to be considered useful? =20
We can transfer up to ~10Msps at 16 bits simplex, or ~5Msps at 16=20
bits duplex (ie, simultaneous tx and rx).  The choice of ADC and DAC=20
specs has obvious impact on the cost.

 - What kind of analogue IO is most useful?  1Vp-p 50ohm input and=20
output?  Transformer coupled?  Filtered?

- I saw on the list AGC mentioned, is this desirable on this kind of=20
module to have programmable attenuation or amplification?

- Has this kind of Native Signal Processing ((c)Intel 199x) at these=20 kind of datarates been tried before? Considering that on a modern PC=20
SSE2 or MMX is available, what are the opinions about being able to=20
have the CPU process data in realtime for common modulation schemes?

Any advice is welcome :-)

=2D -Andy
=2D----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.1 (GNU/Linux)

iD8DBQE+030qjKeDCxMJCTIRAkDVAJ9E0qPBUhw1nhFU5Jme3pLTojfFOQCeMpGe
6td/CaddDzHbGJ2Tsk7AMyc=3D
=3DLtgq
=2D----END PGP SIGNATURE-----



------------------------------

_______________________________________________
Discuss-gnuradio mailing list
address@hidden
http://mail.gnu.org/mailman/listinfo/discuss-gnuradio


End of Discuss-gnuradio Digest, Vol 6, Issue 25
***********************************************






reply via email to

[Prev in Thread] Current Thread [Next in Thread]