Multi-channel surface acoustic wave chemical sensing device

The utility model discloses a multi-channel surface acoustic wave chemical sensing device, which comprises a multi-channel surface acoustic wave chemical sensor, a mixing circuit and an oscillation circuit, and the multi-channel surface acoustic wave chemical sensor is formed by attaching different sensitive films to each detection channel of the multi-channel surface acoustic wave sensor. The multi-channel surface acoustic wave sensor is formed by using piezocrystal as the substrate of the surface acoustic wave sensor, and a plurality of pairs of parallel interdigital transducers are made on the substrate so as to form a plurality of detection channels and one reference channel; each pair of the interdigital transducers comprises an input transducer and an output transducer. The multi-channel surface acoustic wave chemical sensor is divided into a delay linear type and a resonant type. The mixing circuit is used for obtaining a difference frequency signal between each detection channel and the reference channel, and the oscillation circuit is used for driving the interdigital transducers to generate oscillation with a fixed frequency which is used as the working frequency of the multi-channel surface acoustic wave chemical sensor. The utility model can detect various kinds of external gas and the ingredients of chemical substances, and have great significance for production practice.