Popsie had it right the first time. If you want to use a Genie you must have SWM hardware. There are many ways to do this but if you want to be able to receive the DirecTV HDTV programming you will need an open face antenna and I would suggest you get one with the SWM LNB. Nearly all markets can use the SWM SL3 LNB but a few still require the SL5.
Now, if you want full use the of Genie (and a client if you like) but can get by without HD, you can buy a portable automatic antenna as well such as the Carryout. None of the domes style antenna can receive the DirecTV HD channels but you can add a SWM8 kit to these units or even a simple single LNB antenna and your Genie will be fully functional.