Photonic generation of ultrawideband signals based on frequency-dependent gain saturation in a reflective semiconductor optical amplifier.
A novel scheme to generate ultrawideband (UWB) pulses with different polarities is proposed and experimentally demonstrated based on a reflective semiconductor optical amplifier (RSOA). Because the gain saturation in the RSOA is more evident when the injected optical signal has a lower modulation frequency, the RSOA operated at the gain saturation regime can shape a dark or bright return-to-zero pulse to a UWB pulse. An experiment is performed. The fractional bandwidth of the generated UWB pulse is more than 89%. The generated UWB signals with on-off keying format are transmitted in a 20 km single-mode fiber. The power penalty is less than 1.2 dB. Since the RSOA is possibly a key device in wavelength-division multiplexed passive optical networks (WDM-PONs), the proposed optical UWB generator can be used to provide UWB services in a WDM-PON system without significantly increasing the cost.
Microwave Photonics Research Laboratory, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Gang
G
Chen
Shilong
S
Pan