In this talk we will introduce how new mobile base station architectures are evolving not only to meet demand but also to become “greener” since at current rates of deployment, mobile networks are becoming very large CO2 contributors. These new base station architectures are also becoming enablers for new Radio Access Networks (RANs) where the same infrastructure can support multiple radio technologies simultaneously by backhauling their baseband leading towards distributed antenna systems and distributed base station architectures. Some would argue that this represents a paradigm shift towards “cloud” enabled mobile networks. In the talk we will cover the reasons why things are progressing this way, how this is being enabled through technology innovation, and what Agilent has done to meet some of the test and measurement challenges in this evolved 4G wireless communications space.