Switchable UWB pulse generation using a phase modulator and a reconfigurable asymmetric Mach-Zehnder interferometer

Area of Science:

• Optoelectronics
• Optical Signal Processing
• Ultrawideband (UWB) Pulse Generation

Background:

• Ultrawideband (UWB) technology offers high data rates and spectral efficiency.
• Generating tunable UWB pulses, especially Gaussian monocycle and doublet pulses, is crucial for advanced communication systems.
• Existing methods for UWB pulse generation often lack flexibility in polarity control.

Purpose of the Study:

• To propose and demonstrate a new scheme for generating polarity-switchable ultrawideband (UWB) Gaussian pulses.
• To utilize a phase modulator and a reconfigurable asymmetric Mach-Zehnder interferometer (AMZI) for UWB pulse synthesis.
• To achieve controllable generation of both monocycle and doublet UWB pulses with switchable polarity.

Main Methods:

• An optical carrier is phase-modulated by a Gaussian pulse train.
• The modulated signal is processed through a first- or second-order asymmetric Mach-Zehnder interferometer (AMZI).
• The AMZI acts as a differentiator to produce Gaussian UWB monocycle or doublet pulses, with polarity controlled by phase adjustment.

Main Results:

• The proposed system successfully generated Gaussian UWB monocycle and doublet pulses.
• Fractional bandwidths of approximately 177% and 140% were achieved for monocycle and doublet pulses, respectively.
• The polarity switchability of the generated UWB pulses was experimentally verified.

Conclusions:

• The developed scheme provides a flexible method for generating polarity-switchable UWB Gaussian pulses.
• The reconfigurable AMZI offers precise control over pulse characteristics, including polarity.
• This technique has potential applications in advanced optical communication and sensing systems.