Originally Posted by celly
Consider also getting yourself a 3rd party firmware for your router (use with care!). I really like the firmware put out by dd-wrt. These firmwares are generally free for non-commercial use. Not only do they add a lot of features to your router, but you can also dial up the output on your antennae in some applications. Combined with high gain antennae, I've had great results. Don't dial up the output too high or you get errors. Search around the forums on dd-wrt.com for more info.
I would like to know how much output power the phone is set to use at max. If you exceed that on the router, you would just make the UMA unstable since you'd have good incoming reception on the phone, but bad going the other way to the router.