Broadband microwave and optoelectronic devices design by the real frequency technique

This paper presents microwave and optoelectronic devices designed by the real frequency method. These devices are broadband multistage amplifiers, low noise amplifiers, active filters, ultra‐broadband amplifiers with resistive matching networks, active one‐ports for differential structures, laser command circuits, and transimpedance amplifiers. The advantages of the real frequency method are as follows. First, the mathematical formalism is simple and presents no approximations in the various stages of the procedure design. Second, especially for matching networks that constitute distributed elements, this method gives, after the optimization process, several syntheses. Indeed, for a given number of transmission lines and stubs, the synthesis procedure gives all the possible combinations, with their associated different characteristic impedances. So, according to the chosen technology (microstrip or uniplanar, for example), the feasibility of the different characteristic impedances will be taken into account to chose the best synthesis. © 1998 John Wiley & Sons, Inc. Int J RF and Microwave CAE 8: 142–155, 1998.