L-3 Chairman and Chief Executive Michael T. Strianese said in prepared remarks Tuesday that the divestiture of its National Security Solutions unit will allow the company to sharpen its focus on its more profitable defense electronics, communications and surveillance and reconnaissance systems businesses. CACI said the deal, expected to close by the end of March, is expected to add roughly $1 billion in annual revenue and expand the company's presence in enterprise information technology, intelligence services and key market areas.