Computer assisted design to develop functional device and modules for wireless systems

Computer assisted design in conceptional phase is very useful for not only reducing development cost, especially human resource cost, but also creating a novel function. Since the performances of microwave devices and circuits can be precisely simulated by using Maxwell´s equation and electrical circuit theory, conceptional design by computer is very useful for these devices and circuits. This report explains the technologies for automatically generating an antenna structure and a circuit configuration that satisfies the specifications of various wireless systems. These technologies enable us to provide actual products without the knowledge of a senior antenna engineer who has had a very tough and long training. Our design technologies are categorized into brute-force methods for randomly generating antenna structures or circuit configurations and calculating their electromagnetic performances or RF characteristics, i.e., power consumption, distortion, and power conversion efficiency. If the performances satisfy the given specifications, these structures or circuit configurations become the candidates of the device or circuit to be designed. Due to the drastic speeding-up of CPU chips and the continuous improvement of numerical algorithms, we have discovered special structures or configurations that reveal the typical functions for various wireless systems. Prototypes of both devices and circuits that were obtained by using our technologies are introduced, and the typical performances for applications of wireless systems are demonstrated.