BTW, I should have mentioned I have a Droid Bionic and I'm in a 4G LTE service area. Also, I tether the phone to my computer via USB and the PdaNet app. That's when I notice the data is interrupted when a call comes in. The data is interrupted when I turn the screen off, also. Call forwarding is the solution, for me.
While using my Bionic and tethering to my laptop using FoxFi or usb with PdaNet, I remain connected and use both when a call comes in and I'm on the phone.