In radio astronomy wider observing bandwidths are constantly desired to provide improved sensitivity and velocity coverage. As observing frequencies move steadily higher with advances in technology these needs become even more pressing. In order to process wider bandwidths, signal processing components that can perform at higher frequencies are required and integrated circuit approaches are an attractive way of addressing this problem. In this book a range of high speed digitiser integrated circuits are designed using an advanced InP HBT semiconductor process and their performance limits analysed. In the complementary area of analogue signal processing a range of high performance analogue multipliers are designed in InP HBT and SiGe technologies, along with an analysis of their noise limited performance. This book will be of interest to technologists involved in the design of current and future Radio Astronomical instruments.