A step recovery diode based UWB transmitter for low-cost impulse generation

In this paper, we present a step recovery diode (SRD) based ultra-wideband (UWB) transmitter. No custom integrated circuits (ICs) are used, and all of the components are commercially available off-the-shelf products, targeting low-cost and fast turn-around. UWB pulses are generated using SRDs, and pulse position modulation (PPM) is implemented by a microcontroller. Detailed analysis and equations for the SRD-based impulse generation are provided and verified with experimental results. This UWB transmitter has a measured full width half maximum (FWHM) pulse width of 213ps, pulse amplitude of 1.6V, and peak power of 17dBm. The data rate is 2.5MHz, which is limited by the maximum clock frequency of the microcontroller. The supply voltage for the entire circuit is 3V, which is compatible with coin batteries. The power consumption of the SRD pulse generator is 57mW, and the total power consumption of the complete transmitter is 70mW.