This paper proposes a systematic approach for designing and modeling letter-shaped microstrip ground slots. Twenty-three structures are investigated. For each one, a geometrical circuit model is developed. Interestingly, 21 letters have unique s-parameters (electromagnetic [EM] print). Results are confirmed by EM simulations and measurements. These results may pave the way to new applications, e.g. microwave character recognition, letter-based microwave circuits, or new radio frequency identification (RFID) structures
Design of a New Radio-Frequency Switch Topology with Very Low Polarization Current
