What in the World Is Q? [[Distinguished Microwave Lecture}

Everyone acknowledges that quality factor (Q) works as a functional starting point for high-performance RF system design. Nonetheless, students and young engineers can be puzzled by how best to exploit Q?s efficacy in topology creation or circuit parameter optimization. This is because we encounter ambiguous expressions of Q appearing in different places and in various publications [1]. We might, then, wonder how many independent-looking Q formulations there are in our field and how they are physically related. With such a basic (but burning) question in mind, this article knocks at the door to the mysterious world of Q.