This book compiles and presents the research results from the past 5 years in mm–wave Silicon circuits. This area has received a lot of interest from the research community including several university and research groups who have demonstrated record high frequency performance using standard silicon based technology such as digital CMOS and SiGe HBTs. Since many previous expensive mm–wave systems based on III–V technology can now be replaced with silicon, mm–wave based mass market consumer products have been developed. In particular high speed data and auto motive radar are two such applications.This book covers device modeling, circuit building blocks, phased array systems, and antennas and packaging. It focuses on the techniques that uniquely take advantage of the scale and integration offered by silicon based technologies.