RF and Microwave Circuit and Component Design for Wireless Systems

CHAPTER THREE

Overview of Active Devices and Circuit Technologies

This chapter briefly describes several solid-state devices and their circuit fabrication technologies for wireless applications covering UHF to millimeter-wave frequencies. Each system requires several RF functions including switching, amplification, mixing, filtering, sampling, dividing, and combining. Some of these functions are realized using solid-state devices and passive components while the others are obtained using only passive circuits. The fabrication of these circuits requires the use of one or more technologies including printed circuit board, thin, thick and cofired ceramic, monolithic integrated circuit, and multichip module. Their salient features such as cost, manufacturability, and physical and electrical characteristics are reviewed and compared in this chapter. No attempt is made to single out a particular circuit type as a preferred technology, as there are several current and emerging applications with conflicting requirements and these technologies are at different levels of maturity at various companies/laboratories.

3.1 ACTIVE DEVICE TYPES

Several solid-state devices are being used to develop wireless circuits including silicon bipolar junction transistors (BJTs), silicon metal-oxide semiconductor field effect transistors (MOSFETs), laterally diffused metal-oxide semiconductor (LDMOS) transistors, GaAs metal semiconductor field effect transistors (MESFETs), or simply FETs, both GaAs- and InP-based ...