Re: [Discuss-gnuradio] Re: in-band signaling project overview

[Jeff Brower]

Brian-

> On 10/12/07, Jeff Brower <address@hidden> wrote:
> > I think the biggest concerns with Cyclone I are lack of multipliers and low 
> > amount of
> > internal mem (26 kbyte for the EPC1C12).
> 
> Understandable, but also remember that a CORDIC can perform a
> multiplication if you want it pipelined - and if you have a 64MHz
> clock with data coming out at 1Msps, you can perform a 64-tap FIR
> filter with only 1 multiplier instantiated.
> 
> I can see where it is a concern, but it should be able to be
> circumvented relatively easily.  I think a simple rake receiver might
> be possible at something like 1Msps and a 64MHz clock in that FPGA.
> 
> > 802.11b (more specifically VoIP-over-WiFi), GSM (EDGE), and eventually 3G 
> > (HSDPA)
> > waveforms.  I've seen discussions and specific deadline figures for 
> > 802.11b, but not
> > yet for the others -- do you know any web pages that show comparisons?  
> > Thanks.
> 
> I have not seen discussions with regards to those times, but I think
> GSM and HSDPA will be difficult strictly from an encryption
> standpoint.  I thought the algorithms used for those protocols were
> under wraps and portions of the key are in your SIM card?

If you own both ends (or maybe better said "if it's your data in the first 
place")
this is not an issue.

> As a curious note, why do you think there is a big push to do
> standards that are out there and already implemented efficiently in
> dedicated silicon?

I work mostly in the infrastructure side of things.  I'm not sure why people are
pushing to build things like their own software-based GSM receiver -- that's a 
good
question actually.  In my area, as one example, typical basestations cost 70 to
100k.  An SDR server with a PCI/PCIe card containing an FPGA + some DSPs could 
reduce
this cost by a factor of 10.

> Do you have any intention on creating your own MAC protocol?

No.

-Jeff