According to sources reporting to Reuters, the U.S. Department of Justice is set to announce its approval of search giant Google’s purchase of smartphone and tablet manufacturer Motorola Mobility. Google is purchasing Motorola in an effort to secure its patent portfolio in order to bolster defense of Google’s Android operating system from the patent wars that have been marching through the mobile industry. Android has been under heavy attack from the likes of Apple as well as smaller players, and it is thought that Google will use the newly acquired Motorola patents to force its competitors into backing off or inking licensing deals with more favorable terms.