A new development of an equivalent circuit model for magnetostatic forward volume wave transducers

A three-port equivalent circuit model of microstrip transducers used for the generation and detection of magnetostatic forward volume waves (MSFVW) is derived from fundamental physical considerations. In this circuit model, each microstrip MSFVW transducer is modeled as a three-port circuit incorporating a frequency-dependent series reactance, a frequency-dependent lossless transformer, and a lossy transmission line. Circuit parameters are determined in closed form by the use of solutions of pertinent boundary-value problems. The effects of parasitics, for example, capacities of bonding pads, are easily taken into account. Some typical transducer configurations are analyzed numerically. The three-port model developed is in excellent agreement with experiments. The model can be applied directly to nonuniform arrays of microstrips weighted by varying the separation between strip centers and the widths of successive strips or reversing the current direction of some groups of strips