yes and no, it has nothing to do with directv, what you want to do is rebounce the internet off your aircard into a router, and connect the bbdeca to that, you cant use your pc as a host.
aslo, check with your aircard provider, this maybe against their tos or aup, and watch your bandwidth limits, ondemand is going to destroy them lol. An aircard is supposed to be used to allow internet access to a pc, not power a satellite internet connection. It will work but not as well as you are hoping it will, and your ping is going to be horrible.