You should decide the type of usage whether its Outdoor or Indoor. BSNL provides Outdoor CPE where the signal is weak in indoor area(House, etc). If you near the Transmitter, you can go for USB CPE. You cannot use the USB CPE while you on the road.Because the wimax technology is based on 4G and this service provided by BsNl is exclusively for rural areas, so obviously there is no BTS in URBAN areas.