Open AccessGeneralised relations between P ‐ and Y ‐matrices and their applications
Author(s) -
GuerraPulido Jaime Octavio,
PérezAlcázar Pablo Roberto
Publication year - 2014
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/joe.2014.0215
Subject(s) - admittance parameters , transducer , matrix (chemical analysis) , surface acoustic wave , port (circuit theory) , voltage , admittance , acoustics , coupling (piping) , interdigital transducer , physics , electrical engineering , topology (electrical circuits) , materials science , electrical impedance , engineering , metallurgy , composite material
The P ‐matrix is commonly used to analyse surface acoustic waves (SAW) elements such as the interdigital transducer (IDT) but, when some IDTs are connected through their acoustic ports, their frequency response could be calculated easily in terms of their admittances. Instead of the P ‐matrix, Y ‐matrix also allows coupling of the system to another electric or electronic device. Here, the authors present a general method to obtain the Y ‐matrix (with size N × N) of a SAW device with N electrical terminals connected to N different voltage sources. This method considers the reflections from the edges or any other non‐electrical elements that can cause reflections beyond P ‐matrices. In addition, it has been shown that when there are no reflections and there are two P ‐matrices, this method converges to well‐known previous results. Furthermore, the authors present two cases that could be used to analyse a SAW device: the input admittance and the equivalent P ‐matrix for a SAW device when a Y ‐matrix is connected to the electrical port of the SAW device. Also, the authors have calculated the acoustic relations for two SAW devices connected through their electric ports. Furthermore, these methods are exemplified through their application to a SAW system composed of three different IDTs and to an IDT and an inductor connected to its electrical port.