| Radio frequency integrated circuit (RFIC) design is an exciting area for research or product development. Technologies are constantly being improved, and as they are, circuits formerly implemented as discrete solutions can now be integrated onto a single chip. In addition to widely used applications such as cordless phones and cell phones, new applications continue to emerge. Examples of new products requiring RFICs are wireless local-area networks (WLAN), keyless entry for cars, wireless toll collection, Global Positioning System (GPS) navigation, remote tags, asset tracking, remote sensing, and tuners in cable modems. Thus, the market is expanding, and with each new application there are unique challenges for the designers to overcome. As a result, the field of RFIC design should have an abundance of products to keep designers entertained for years to come.
In this book there is a lot of detailed academic exploration of some important high-frequency RF bipolar ICs. One might ask if this is important in design for application, and the answer is yes. To understand why, one must appreciate the central role of analog circuit simulators in the design of such circuits. At the beginning of my career (around 1955–1960) discrete circuits were large enough that good circuit topologies could be picked out by breadboarding with the actual parts themselves. This worked fairly well with some analog circuits at audio frequencies, but failed completely in the progression to integrated circuits. |