A joint party spokesman says the changes include limiting any media operator to owning two out of three outlets in any metropolitan or regional market.
Radio stations will be required to broadcast four and a half hours of local and live content in regional areas.
And one of the two digital channels, channel B, will have special access arrangements to guarantee diversity of content.
Barnaby undecided
But rouge Nationals senator Barnaby Joyce says he is "still working" on whether he can back the proposed new laws and warns he could cross the floor on any amendments to the legislation.
"Diversity of ownership is important - it's probably one of the most important things you've got in a democracy," Mr Joyce said.
Senator Joyce flagged putting up his own amendment, with or without government support.
He said he wanted to see legislation committing media watchdog, the Australian Communications and Media Authority (ACMA), to regular checks on media diversity.
"We want it in legislation, not regulation," he said.