I think it is at least quadband HSPA. Don't know about the LTE frequencies or whether it will support the rare 1700mhz HSPA frequency. Here is a New York Times review, but it is light on the technical specifications:
http://www.nytimes.com/2013/08/02/te...anted=all&_r=0
Here is a Wired article:
http://www.wired.com/gadgetlab/2013/...ory-of-moto-x/