The instant disclosure provides a detection device and detection circuit thereof. The detection device includes a detection circuit, a signal source and a signal analyzing unit. The detection circuit has a sensing oscillator to form a first signal with a first frequency. The signal source provides a second signal with second frequency. The detection circuit produces an output signal including its intermodulation signals based on the first signal and the second signal. The signal analyzing unit produces an enhanced sensitive detection result in accordance with the change of the frequency of the intermodulation signals.一種檢測裝置及其偵測電路。檢測裝置包含偵測電路、信號源、及信號分析單元。偵測電路具有感測震盪器以形成具有第一頻率的第一信號。信號源提供具有第二頻率的第二信號。偵測電路利用第一信號及第二信號的互調作用產生互調信號於輸出信號中。信號分析單元根據互調信號的頻率變化產生一提升靈敏度檢測結果。
