We experimentally demonstrate a photonic microwave frequency measurement based on polarization interference by measuring DC voltage. Time delay is introduced into two electric signals which serves as driving signals of the parallel Mach–Zehnder modulators. After polarization interference, the amplitude of DC output is related to the microwave frequency. Thus, the system can identify the input frequency avoiding high-speed and wideband detectors. In the measurement with one polarization interference, the measurement range and resolution can be optimized using wavelength division multiplexing. The measurement range of 0-26 GHz with measurement errors within 0.2 GHz and 26-40 GHz with errors within 0.4 GHz are achieved. In the measurement with orthogonal polarization interference, the measurement range and resolution is tunable by adjusting the time delay. The measurement range of 2.1-9.6 GHz with measurement errors within 0.3 GHz and 5.4-23.4 GHz with errors within 0.35 GHz are achieved.

我们通过测量直流电压实验性地证明了基于极化干扰的光子微波频率测量。将时间延迟引入两个电信号中，这两个电信号用作并行Mach–Zehnder调制器的驱动信号。经过极化干扰后，直流输出的幅度与微波频率有关。因此，系统可以避免高速和宽带检测器而识别输入频率。在一个偏振干扰的测量中，可以使用波分复用来优化测量范围和分辨率。可以实现0-26 GHz的测量范围（具有0.2 GHz的测量误差）和26-40 GHz的误差在0.4 GHz范围内。在正交极化干扰的测量中，通过调整时间延迟可以调整测量范围和分辨率。可以实现2.1-9.6 GHz的测量范围（测量误差在0.3 GHz之内）和5.4-23.4 GHz（测量误差在0.35 GHz之内）。