A new SAW-resonator with electronically switchable resonance frequency

A new two-port SAW-resonator is presented. Its transmission frequency can be switched between two discrete resonances by changing the electrical termination of additional transducers within the resonator´s cavity. This can be done by mechanical switches or by FETs which allow for electronical switching with low power consumption. The device can be applied to provide a simple change of a transmitters carrier frequency. It may be also used for low-cost, low-bit-rate frequency shift keying transmission systems. Extending the principle to more than two resonances a switchable oscillator for channel selection can be realized. In this case an advantageously low oscillator´s phase noise is achieved. This is due to the high quality factor of SAW-resonators