Photonic ultrawideband impulse radio shape modulation based on dual-filter tuning.

A simple and flexible photonic scheme for the generation of ultrawideband (UWB) pulse shape modulation based on dual-filter tuning is proposed and experimentally demonstrated. By launching a Gaussian signal into a phase modulator, the UWB polarity-switchable monocycle is generated at the output of two optical bandpass filters by adjusting the central wavelengths of the dual-filter appropriately. The doublet pulses with inverted polarities are obtained by combining the pair of UWB monocycle pulses under proper time delay. Meanwhile, with a predefined code pattern and controlling the optical path difference of the two monocycle pulses, the pulse shape modulation can be performed.