A novel small‐signal detection method using divergence properties of second‐order linear differential equations

Abstract A novel small‐signal detection method that focuses on detection rather than measurement is proposed. It is particularly useful when a sensor is implanted within a living body. Unlike conventional methods, the proposed method detects signals by converting the input signal into a frequency change of an oscillator and monitoring the change in frequency. Its main advantage is the possibility of greatly reducing the circuit size and power consumption compared to conventional methods. To verify the proposed method, a simple implementation experiment using an actual device is performed. Consequently, pulse signals were successfully detected using the proposed method. It is believed that with appropriate implementation, the circuit can detect many types of signals. It is expected that the proposed method can facilitate the collection of small‐signal data and promote its analysis, thereby contributing to the development of various fields.