Frequency-doubled Microwave Photonic Phase Shifter with Frequency up-/down Conversion without Optically Filtering

A frequency-doubled microwave photonic phase shifter with frequency up-/down-conversion is proposed and theoretically investigated, which is verified by simulations. In the scheme, two parallel Mach-Zehnder modulators (MZM), cascaded with an integrated Mach-Zehnder modulator (DPMZM) and a phase modulator (PM)by a 2×2 optical coupler (OC), are used to generate the ±2nd-order sidebands adjustably, and a PM is used to phase shift one of the two lightwaves. After photodetection, the generated frequency-converted signal with a continuously tunable phase shift from 0 to 360deg can be generated by adjusting the RF driving signal and the DC bias voltage of the DPMZM, and the DC voltage of the PM. Simulation results demonstrate that both 360-deg continuously tunable phase shift and frequency conversion can be implemented. The spurious suppression ratio is more than 40dB in the electrical domain and the conversion efficiency is −18 dB