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RE: Proposal: SDR-DSP receiver (was: Re: Cube sat and DSPs (was Re: cube sat))

Sign me up.  The more the merrier.

AB2KT and I have written for Linux and Windows, using gcc, fftw,
VSIPL a signal processing chain to do ssb,cw,am (synchronous and
rectifier), and fm.  For Linux, I am using Qt,  Python/Tk, and some
others to build GUI interfaces and we will be using XML to a command
interpreter.  We are using Hamlib to control the SDR-1000.  We want
to have it remoteable the day we give it out. It is multithreaded from
the get-go.   This code is not yet released because I want to do the
first cut at the GUI, Frank and I want to do a first version of the
command interpreter, and to get it all glued together but our goal
is finished with round 1 by the end of April.  You will not likely
be ready for Alpha test by then so you will have code awaiting you.

For your information, the USRP, Universal Software Radio Peripheral,
is in alpha test.  I have one and will fire it up and start working
with it once the SDR-1000, SDR-Linux code is out.  It has a 65 Mhz
A/D and CIC downsampling filters being done by FPGA and lastly,
a USB 2.0 interface to the computer.  This is an open hardware and
open software project.   Given your desire to user a wider part
(more bits), I could easily use it and would welcome that.


-----Original Message-----
From: owner-AMSAT-BB@AMSAT.Org [mailto:owner-AMSAT-BB@AMSAT.Org]On
Behalf Of Achim Vollhardt
Sent: Tuesday, March 30, 2004 6:03 AM
To: AMSAT Bulletin Board
Subject: Proposal: SDR-DSP receiver (was: Re: [amsat-bb] Cube sat and
DSPs (was Re: cube sat))

Hello Hams,

 ----------------------  SNIP ---------------

Proposal is to is a 65 MSPS ADC with the digital down converter and
DSP.. so possible reception would be somwhere between 0.1 and 30 MHz.
Perhaps direct reception of the aliased image of 144 MHz (at 14 MHz)
would be possible as well.. a common problem like bad large signal
performace is negligible as we deal with sat-downlinks.. we don't have
large signals!!

What I have:

- a basic idea how this works
- some sample devices
- experience in layouting and a PCB company at hand.. :)

What I need:
- more people willing to join (!)
- some techies to iron out the bumps.. ;)
- some DSP coders.. I started digging into it but with some experience,
things like SSB, FM, AM and CW demodulation is a piece of cake..
- more ideas: this baby could also handle PSK31 or high speed PSK
decoding (anybody interested in decoding the deep-space probes?),
digital voice encoding (with forward error correction!).

I think this is a real challenge.. when keeping all open-source, this
could be a wonderful project pushing the limits !

Hpoing to trigger some discussion..

73s, Achim, DH2VA

Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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