You can't use Routers with built-in ADSL modem for anything other than ADSL based comms. The reason is that they route between the WAN connection (ADSL Modem) and your LAN.
I am guessing that your wireless Broadband supplier supplies an DCE device that connects directly to your PC. If it uses USB forget it. However if it uses Ethernet then you need a so-called Cable Router. That is to say a router WITHOUT built-in ADSL modem.
Terry