A simple photonic approach for joint measurement of frequency and angle-of-arrival

We proposed and experimentally demonstrated an approach for the joint measurement of frequency and arrival-of-angle (AOA). This method maps frequency and AOA-dependent phase difference onto power in the form of a cosine function by introducing a delay operation. By tuning the delay, the delay values corresponding to the maximum and minimum power can be identified, and two parameters to be measured can thus be easily derived through conversion equation. Theoretical analysis is given in detail. In proof-of-concept experiment, the system achieved a full 360° phase difference measurement, with a maximum error of 5.9°. The frequency measurement range spanned from 1 GHz to 10 GHz, with a maximum error of 3.5 %. The proposed scheme exhibits the advantages of simple operation, low cost, and unambiguous phase difference measurement, which provides a new perspective for the joint frequency and AOA measurement.