radio transmission on 2.4 - 2.5 ghz 1

You need a pair of transmitter and receiver with antennas
to match your -- unspecified -- requirements.

<nbucska@pcperipherals.com>

It's unclear why you have to use those wavelengths, but if you must, they're assigned to cell phones and maritime/aviation radios.

I would think you're cheapest solution might be to interface a couple of cell phones to whatever it is that you're transmitting/receiving

TTFN

You are close to an unlicensed band. That is good news. The bad news is that the unlicensed band is also power limited. If you do your link analysis you will see that your data rate will be very small and your coding gain must be very high to use the frequencies you want and the distances you need. You should look into pre-built purchased units. If you do not have clear requirements or a background in this it will be far less expensive that trying to design and build it yourself. However, if this is a school project you will have a lot of challenges. First find out exactly where your frequency reauirement comes from and what the license requirement is in your country. next is your link analysis.
Good Luck!
John Solar