A demultiplexing scheme based on semiconductor optical amplifier(SOA)and optical filter for optical time division multiplexing differential quadrature phase shift keying(OTDM-DQPSK)system is proposed and investigated experimentally.With only a common half baudrate electrical clock modulated 33%duty cycle return-to-zero(RZ-33)optical clock signal as pump,this scheme is cost-effective,energy-efficient,and integration-potential.A proof-of-concept experiment is carried out for the demultiplexing of a 2×40-GBd OTDM-DQPSK signal.Error-free performance is demonstrated,and the average power penalty for both channels is about 3 dB.
A scheme for photonic generation of ultra-wideband (UWB) pulses using a semiconductor optical amplifier (SOA) and an electro-absorber (EA) in parallel is proposed and numerically demonstrated. By adjusting the time delay between two pump signals incident into the SOA and the EA, we can obtain monocycle pulses with reversed polarities and different bandwidths. The proposed method is flexible in pulse shaping and easy in practical optimization.