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A microctectromechanical system (MEMS) integrates electrical and mechanical functions in a single component using microfabrication or micromachining technology similar to semiconductor integrated circuit processing. MEMS has proved to be a revolutionary technology in many application arenas, including accelerometers, pressure sensors, micro-optics, inkjet nozzles, optical scanners, and fluid pumps. MEMS devices employed in radio-frequency applications are termed RF MEMS. Assembly techniques are used for transferring MEMS devices to an RF circuit on a different substrate, or for fabrication of nonplanar MEMS structures.

Microwave switches, phase shifters, and attenuators are three important "control" circuits used extensively For controlling the signal flow at microwave frequencies. A single phased array radar system, for example, may use thousands of these circuits for precise electronic control of the radiated beam. The current chapter describes microwave control circuits using semiconductor devices. However, many of these circuit configurations and design approaches are applicable for MEMS circuits also. In the passive mode of operation, MESFETs are used as passive two-terminal devices, with the gate terminal acting as a port for the control signal only.

This introductory chapter serves to set the context of the analysis of circuit-antenna modules. The development of such modules is described together with some explanation of the terminology currently used. A glossary of types is presented that aims to show the range of configurations currently being studied and to highlight the design challenges. The likely design parameters are then given, together with a review of the design process in which analysis tools have to serve. Finally, an overview of the book chapters is given. [ABSTRACT FROM PUBLISHER]

In order to develop designs for integrated circuit-antenna modules, an appreciation of the computer-aided design process is necessary. This chapter starts with a discussion of the design process in general. Conventional design, computer-aided design, and knowledge based design approaches are outlined. CAD procedures for microwave circuits and printed microstrip antennas, as practiced separately, are described. Then the discussion converges on CAD considerations for integrated circuit-antenna modules implemented at various levels of integration (nonintegrated, partially integrated, and fully integrated). [ABSTRACT FROM PUBLISHER]

The multiport network method offers enhanced accuracy compared to simple equivalent circuit methods and can be integrated with active device models. This chapter introduces the concept of the multiport network model as developed for single-layer and two-layer microstrip patch antennas. Applications of the multiport network method to integrated circuit-antenna modules are discussed. [ABSTRACT FROM PUBLISHER]

The book is completed by a short chapter in which some conclusions are drawn. The current status of computer-aided design tools is summarized from the earlier chapters. Some thoughts on the likely future challenges that analysis will face are then given. The chapter is then closed by comments on what now remains to be done to present designers with a full and flexible array of software to facilitate fast and accurate design. [ABSTRACT FROM PUBLISHER]