The Federal Communications Commission (FCC) has approved the rules to come into force next January, when auctions are due to be held for certain airwaves.
They will open up access for consumers to use nearly any wireless device they like to use broadband services and switch mobile telephone service providers without having to buy a new hand set.
"This laboratory of free innovation has the potential to liberate consumers from the restrictive and uniquely American 'locked handset' regime nationwide," said the non-profit Computer and Communications Industry Association (CCIA), which lobbies for open markets in telecommunications and other technologies.
The FCC said it had adopted a revised plan for the 700 MHz band spectrum, which is currently occupied by television broadcasters but will be abandoned in the country's switch to digital television in 2009.
Under the new rules, the band will be made available to wireless services in a pro-consumer move "to facilitate the availability of new and innovative wireless broadband services for consumers," the FCC said.
This will "help create a national broadband network for public safety," enabling better communications in emergencies, preventing problems which can occur when different emergency services use different communications equipment.
Such problems came to light in the chaos following the terrorist attacks of September 11, 2001, and the disastrous flooding that struck the city of New Orleans in 2005.
The measures will also shake up the US market, where mobile phone service providers can restrict the type of handset their subscribers use by applying exclusive standards.