Irvine-based Microsemi, a manufacturer of analog and mixed signal semiconductors, announced today that it has acquired the Defense & Security Business of Endwave Corporation, a developer of high frequency RF circuits. According to the firm, it will pay $28M in cash plus assume specific liabilities for Endwave's defense and security business, which supplies RF semiconductors to Boeing, Lockheed Martin, Northrop Grumman, and others. Microsemi explained that it will expand the unit's products into new, related markets such as satellite and space, and that it believes the acquisition will be accretive immediately to the firm.