I do a lot of work with DSP and I am looking for an inexpensive down converter so as to down convert from the FM band to some intermediate frequency. Not necessarily to standard FM 10.7MHz but something lower that I can choose. The reason that I want to do this is that I want to be able to "grab' up to 4 FM "stations" at a time and do the discriminators in DSP using something called a polyphase channelizer, after A/D conversion, which I have done in simulation. Yea, I know that there might not be 4 active FM stations within 200KHz of each other but I'll deal with that problem later.
I thought of using the RF front end to the venerable RTL-SDK, just taking the output of the E4000 RF IC bypassing the decoder but that part has a limited bandwidth. I am not sure if there is too much roll-off past the original FM station that it is tuned to.
The bottom line question is, is there a SDR that has an RF front end that I could use to down convert a group of FM stations? I did not want to go off half cocked before asking the experts. Perhaps there is a commercial unit available that has an IF out with a wide bandwidth? I suppose that I could get out my ARRL Radio Handbook and build one myself but I want to see what I can start with.
Thank You Tom