PA Design in Silicon (SiGe & CMOS) and Other III-V Processes for Advanced Beamformed Applications

5G will require a drastic reduction of the power consumption and offer a more flexible use of the RF to mm-wave spectrum. Higher capacity needs will be addressed by new RF and mm-wave systems with high-density small cells, advanced MIMO and new multiple access schemes. To meet these challenges, 5G will use beamforming techniques with phased-array transceivers to improve the quality of transmission, reduce the user interferences and extend the network coverage. One of the main challenges for 5G PA is still to deliver maximum output power with maximum efficiency and high linearity. However, the next real challenge is to work with a high number of individual elements within their own environment, ensuring a common global performance. This is more a relationship between reliable and stable individual performances regarding global antenna one. To reach these goals, we have to properly choose the PA design and technology regarding individual target but also global one. For instance, what if a limited number of PA does not see the same load (VSWR) as the other ones? What about reliability? What about ruggedness? Where to put the priority in design and technology choice? Do we need to look for the best elementary PA or the best phase array one? In this talk, we will debate our recent RF and mm-wave development done in CMOS SOI and SiGe to make an elementary PA easily integrable with a high number of PA onto a common phase array antenna.