You may get more choice if you use 2.4Ghz, the band that is used for Bluetooth and 802.11. There are many chip companys making complete radio solutions. (CSR, infineon, Silicon wave, Broadcom to name a few).
hello
My mean was 2.4GHZ,I need to find a Total System Solution for this .
But I do not know how to select and I only want to send data and receive at this frequency ,I do not want to use complex protocols like as bluetooth ,I want to use my custom protocol for my application.
You can just go to maxim-ic.com. I suggest you just evaluate their 2.4 GHz solution for WLAN. Those are cheap, tested. And you can apply to 2.5 GHz without problems. You need to choose the technology like SiGe, or similar.