Highly Accurate Measurement of Multi-microwave Signal Frequency Based on Diamond NV Centers

The measurement of microwave signal frequencies is indispensable in modern communication systems. To achieve high-precision microwave frequency detection, this study proposes a novel microwave frequency measurement method based on diamond nitrogen-vacancy (NV) centers. By utilizing NV centers as frequency mixers and integrating continuous heterodyne detection with Fast Fourier Transform (FFT) analysis, this approach enables high-accuracy synchronous identification of multiple microwave frequencies. Systematic validation through power adjustment of the measured microwave signals demonstrates the method’s applicability under varying power conditions. Experimental results reveal a frequency resolution as high as mHz-level, with the capability to simultaneously identify multiple microwave signals at distinct frequencies. This breakthrough provides critical technical support for interference signal recognition, radio-frequency identification (RFID), and Internet of Things (IoT) engineering applications.