Frequency stability of a crystal resonator for biosensors

This paper describes oscillation frequency stability of a crystal sensor for biosensors used for detection of dioxins, PCB, environmental-stressors, and marker proteins for infections. Present frequency stability is about 0.1 ppm in 9 MHz. Design technology for communication is applied to the crystal unit and oscillator circuit as a sensor. We prepared a crystal unit for filters in an oscillator circuit, and adopted a method that engenders oscillation frequency stability. That method demonstrates performance of 5 ppb at 9 MHz and 14 ppb at 155 MHz.