A unit of Liberty Media Corp. said Thursday it would buy out a satellite system from its partners for about $46 million and invest more money in the business to provide corporate and government customers with secure access to high-speed networks.

Astrolink International, as the system is known, was formed in 1999, with Liberty Satellite & Technology Inc. owning a little less than one-third and the rest controlled by Northrop Grumman Space & Mission Systems Corp., formerly known as TRW Inc., Lockheed Martin Corp. and Telespazio SpA.

The transaction is expected to close by Oct. 31, but still requires regulatory approvals and funding deals with other investors, Liberty Satellite said in a statement.

Liberty Satellite, based in Englewood, Colorado, agreed to pay about $43 million of cash and to issue $3 million of Series A common stock for the Astrolink assets and its launch contracts. As part of the deal, Astrolink signed agreements with Lockheed and Northrop to complete two satellites. The deal also settles all claims related to Astrolink's earlier termination of procurement contracts and from other third-party creditors, Liberty Satellite said.

Liberty Media, run by cable pioneer John Malone, said it would buy up to $55 million of Liberty Satellite Series B common stock at the deal's closing.