DISTRIBUTED SURFACE ACOUSTIC WAVE RESONATOR AND SURFACE ACOUSTIC WAVE SENSING SYSTEM

The present invention discloses a distributed surface acoustic wave resonator and a surface acoustic wave sensing system, the distributed surface acoustic wave resonator comprising a first antenna, a matching network, a reflection grating, and an interdigital transducer, with at least said reflection grating and said interdigital transducer assembled on a piezoelectric substrate, said matching network comprising an optimal matching network which is composed of at least one capacitor and at least one inductor, said optimal matching network also connecting a switch circuit in parallel, said switch circuit comprising multiple branch circuits connected in parallel, each branch circuit comprising at least one capacitor and/or one inductor, said each branch circuit of the switch circuit also comprising a switch to control the conduction status of that branch circuit. In the distributed surface acoustic wave resonator of the present invention, when the matching network connects different branch circuit, the corresponding resonator corresponds to one central frequency, i.e. the central frequency of the resonator can be changed. The circuit structure is simple and occupies small space.