Re: [Discuss-gnuradio] Analog Devices RF RX/TX subsystems for Spartan-3AN FPGA

[Eric Brombaugh]

On 06/17/2010 09:58 AM, Elvis Dowson wrote:
> Hi,
>           I would like to design a custom board based on the Spartan-3AN FPGA, 
> based on the Spartan-3AN FPGA Starter Kit, but would like to build my own RF 
> front-end.
>
> http://www.analog.com/en/rfif-components/rxtx-subsystems/products/index.html
>
> If I look at the AD9874 IF-to-Bits RX subsystem component
>
> http://www.analog.com/en/rfif-components/rxtx-subsystems/ad9874/products/product.html
>
> it contains an ADC and a whole bunch of other stuff.
>
> Could someone help me by pointing out what other components or parts I should 
> be looking at to build the RF receiver front-end to start with, assuming that I 
> am going to learn from the USRP2 design, and the fact that it already has the 
> Spartan-3AN FPGA, and I'm going to build my own RF front-end?

Designing an RF frontend from scratch sounds like a challenge, and the 
AD9874 requires a fair amount of support circuitry. Have you considered 
trying something a bit more integrated? How about this:

http://sdrtrack.drupalcafe.com/

While that project isn't getting a lot of support lately, there are 
schematics and supporting materials available and the part that it's 
based on is highly integrated and fairly inexpensive:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=296-21570-1-ND

Eric