The steps to flash this are as follows (make sure you have the Samsung mobile drivers installed so that your phone can be recognized by Odin):
-Disconnect your phone from the PC, if it's connected.
-Completely power down your phone, not reboot, or boot into download mode, but power down.
-Power back on your phone into download mode (vol+down,power,home)
-Open Odin (3.04/3.09) and connect your phone to the PC. At this point, Odin shoudl say <<Added>> or something of the sort.
-Uncheck "auto reboot" from Odin.
-Load up this NH7 baseband tar image into the PDA (3.04) or AP(?) (3.09) section of Odin, and flash.
-Once complete, disconnect your phone, remove the battery for around 5-10 seconds, then power your phone back on into download mode.
-Check "auto reboot" from Odin.
-Flash again, then let your phone auto reboot back into android.
-You should either receive an "android has been upgraded" message or you can verify you're on the new baseband by checking settings>about
Note: Steps were taken from the unlock thread in general.
Download NH7 baseband/modem: Here