1994 Ford Explorer Noise from Front End

I bought this vehicle new and this vibration noise in the front right tire started. Sounds like a rubbing noise. When I bought new tires. After having it realigned, balanced etc I had another set of tires put on & it improved somewhat but still persisted. I had all tires rotated & the noise has gotten progressively worse. You can hear the noise as the tire goes around.
Could it be a bearing or brake rotors?
Thanks.