ITT Exelis [XLS] on Monday said it has agreed to acquire C4i Pty. Ltd, an Australian company that develops and provides communications software for air traffic management systems and mobile communications for commercial, defense and homeland security customers.

The deal, worth $16.8 million, is expected to close in the first quarter of 2013. C4i has about 45 employees and its sales for the year ending June 30, 2012 were about $9.5 million.

C4i will bolster Exelis’ air traffic management portfolio with the advanced communications software and will also expand its presence in Australia.

C4i’s interoperable communications solutions and engineering talent will complement Exelis’ strong and successful record of integrating, deploying and operating large scale communications networks for our air traffic management, commercial and defense customers,” Michael Wilson, president of Exelis Information Systems, said in a statement. He also said the deal will bring it closer to “our customers and markets of interest.

C4i’s customers include Australia’s Ministry of Defence and others in the utilities, transportation, mining and oil and gas industries, as well as the United States Defense Department and major U.S. defense contractors.

C4i provides Internet Protocol-based voice control and switching solutions that allow for large networks of radio devices to be seamlessly integrated, Exelis said. The solutions allow for an integrated command and control system that enables enhanced safety and efficiency for air traffic control, it added.

Exelis is buying C4i from Australia’s Longreach Group Limited. C4i is Longreach’s only operating subsidiary.