Photonic Generation of Ultrawideband Signals With Large Carrier Frequency Tunability Based on an Optical Carrier Phase-Shifting Method

We theoretically and experimentally demonstrated a novel photonic approach to generating ultrawideband (UWB) pulses with large carrier frequency tunability based on an optical carrier phase-shifting technique by cascading polarization modulators (PolMs) and a polarizer. The UWB pulses are generated by truncating a continuous wave (CW) RF signal into a pulsed signal in a photodetector (PD). The experimental results show that the baseband frequency components and the strong residual local oscillator (LO) signal are well suppressed. In addition, the generated UWB signals satisfy the Federal Communications Commission (FCC) spectral mask very well.