Design of a new optical impulse radio system for ultra-wideband wireless communications

This study presents a novel optical impulse radio (IR) system for generating Gaussian monocycle pulses for ultrawideband (UWB) radio-over-fiber communications. The proposed system consists of a gain-switched Fabry-Perot laser diode, tunable filter, Er³⁺-doped fiber amplifier and a microwave differentiator. This new optical technique can tolerate pulse dispersion and avoid the generation of intersymbol interference (ISI) due to its easily adjustable optical pulse width, and can perform better radio communication in terms of generating the UWB signal. Simulated results indicate that the generated Gaussian pulse signal can provide a bandwidth of several gigahertz for the high-bit-rate transmissions. Moreover, experimental and analytical results demonstrate that the proposed system can generate high-quality Gaussian pulse trains for applying future high-bit-rate UWB wireless communications