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What board you recommend me (the cheapest please)?? but I need at least can connect 2 antennas.
thanks for your reply!!
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It really depends on your full requirements, I would look at what's available on the RF side of things as far as dev boards and see if they can be matched to a particular fpga.
That attached picture is a proof of concept design we did using various dev boards for one of our customers. This is basically a ISM full band software defined radio.
There is only one custom board in the system, and it's a simple interconnect board between the Altera Cyclone III Dev board and the TI L138 dev board.
All the RF was done with various LT boards.
As far as CHEAP, the DE0 Nano could do the trick and has simple 40 pin headers you can wire into, but is the FPGA big enough?? I don't know.
For a proof of concept, tying a bunch of dev boards together works. But make sure you look at all the pieces first. Selecting the FPGA board first could just cost you more money in the long run, if you have to do a custom board to get the other pieces to connect to it. (Or it turns out it doesn't have the capabilities you really required)
I would first start in simulation. Simulate what you need in Matlab or equivalent, then start porting the design over to the FPGA. Once you have a good handle of the all the requirements you have for the system, look at what's available for dev boards.
Altera/Terasic have gone to HSMC connectors as a standard for many of their higher end dev boards. These are nice, because you get get some high performance out of them, but they also means you also need a custom board to work with them. Unless you can find what you need already with HSMC adaptors.
The DE0 and DE0 Nano have just simple 40 pin headers, so they are easy to hand build something, but are they big enough for you?
the Cyclone II DSP dev board has foot prints for 2 ADC/DAC's but it's getting pretty old and costs $1000 (and you would have to hand solder the parts for the Second ADC/DAC channels for your needs..)