Compact Multi-Tone Microwave Photonic Frequency Measurement Based on a Single Modulator and Frequency-to-Time Mapping

We propose a microwave photonic frequency measurement scheme based a dual-polarization dual-drive Mach-Zehnder modulator (DP-DDMZM) and frequency -to-time mapping. A compact frequency measurement system is guaranteed thanks to the use of a single modulator, and multi-tone measurement ability is achieved due to the principle of frequency-to-time mapping. In the proposed scheme, the unknown microwave signal is mixed with a linearly chirped microwave signal with the help of the DP-DDMZM, and the mixing product is selected by an electrical bandpass filter to achieve frequency-to-time mapping. Single and multi-tone microwave frequency measurement are successfully demonstrated in the experiment, and the measurement errors are less than ± 3 MHz.