high frequency RFid Readrs?

I want to start the project of high frequency readers. how can i made and which chip(RFid) is compatible for AVR micro controller.

never worked on AVR dude,
nevertheless...
i think every reader available is compatible... most of them come with dual TTL output...
so either it be a 5v controller or 3v3 controller ..if the module is serial.. it has to work.
. at the most u will be required a level shifter (max232,3232 etc.)

you may use RFID reader modules.. which are moderate in cost and will give you great compatibility with any microcontroller you work on. readers with UART interface are easily available. check nearby stockist and ask how he can help getting one of them..

i need help for making those type of readers.. nearest shops also having that one.. :mad

making a reader??
get the IC.. make a module yourself..

its ok. but i want to know difference between mifare cards and rfid low freq and high freq?