Re: [Discuss-gnuradio] ztex USB-FPGA board

[Luke Kenneth Casson Leighton]

On Sun, Nov 1, 2009 at 1:56 PM, Tim Newman <address@hidden> wrote:
> Luke Kenneth Casson Leighton wrote:
>>
>> http://shop.ztex.de/product_info.php?cPath=21&products_id=28
>>
>> dear gnuradio developers,
>>
>> i was searching on opencores.org to see if there was a SoC that
>> incorporates an FPGA(-like) device with an open core, and i
>> accidentally encountered the above USB-FPGA board.  it has a Cypress
>> CY7C68013A/14A 480mb/s USB-2 Microcontroller and a Xilinx Spartan-3
>> XC3S400 FPGA.  it is also accompanied by a developer board:
>>
>>  http://www.ztex.de/usb-fpga-1/exp-1.1.e.html
>>
>> the price for the USB-FPGA is an incredibly-low $EUR 70, and the
>> developer board is only $20.
>>
>> so my primary question is: is this USB-FPGA board (apart from the
>> issue of connecting to A-D / D-A boards) suitable for use to do an
>> 802.11b transceiver?  is it fast enough?
>>
>> many thanks,
>>
>> l.
>>
>>
>> _______________________________________________
>> Discuss-gnuradio mailing list
>> address@hidden
>> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>
>
> This is a fairly loaded question, as it completely depends on WHERE you
> implement certain portions of the 802.11b waveform.  The primary bottleneck
> is the USB bus, and you can't get 20 MHz of bandwidth over that bus.

 ah - eek! i wasn't anticipating it to be that much.  i was expecting
a much-reduced amount of data.

>  BBN
> and whoever else worked on the current GNU radio 802.11b waveform solved
> this by moving the despreading to the FPGA.  This is just one example.

 ohh, ok - so it's doable - just.... rather technical :)

 thanks for responding, tim.

 l.