Design of pulse synthesizers for the convergence of IR-UWB solutions

This paper presents some techniques to synthesize pulses in the context of IR-UWB. Pulse synthesizers are good candidates when different kinds of pulses are needed to comply with different standards or when the shape of the pulses needs to be modified. Two different approaches are described here. Voltage Controlled Delay Line (VCDL) based pulses are first described. For this family, two kinds of combiners are presented: differential pairs based and H-bridge based. The second one achieves a larger output dynamic but is limited by the use of the VCDL. A second type of H-bridge based synthesizer using VCO is presented. Using both a VCO and a H-Bridge offers the largest synthesis capabilities since it allows large voltage pulses to be synthesized and the pulse duration is not limited. All proposed architectures have been implemented and their measured performances are given for comparison.