Digital frequency control method for MSW oscillators using straightedge resonators

Digital control method for oscillatory frequencies of a magnetostatic wave (MSW) oscillator employing a straightedge resonator without changing the external magnetic field and the circuit parameters of a feedback load circuit is discussed. In this method, additional electrodes are fabricated near or at the edges of the resonator and pin diodes are connected in series. Upon switching the pin diodes on and off, the resonant frequency can be shifted while the oscillation condition is maintained. We constructed an oscillator using a straightedge resonator with one additional electrode near each edge and could observe a shift of the oscillatory peak as predicted by our equivalent circuit model. We also examined a condition for realizing optimum frequency shift when the oscillatory frequency is controlled by the pin diodes