An ultra low-power low-cost gaussian impulse generator for uwb applications

Abstract

a new fully integrated ultra low-power pulse width adjustable Gaussian impulse generator using a low-cost 0.18 mum UMC CMOS process was designed and measured for ultra wideband (UWB) transmitter. The Gaussian impulse generator integrates a square-wave generator and an impulse-forming circuitry together in a single chip. The square-wave generator produces a square wave with sharp rising/falling edge, which is fed to the impulse-forming circuit. Simple CMOS inverter and NOR block are employed for the Gaussian impulse formation instead of a complex analog circuit formation, which must use resistor, capacitor and inductors (Zheng et al., 2002). Due to this CMOS Gaussian impulse generator all digital features, the generated pulse-width is easily adjustable from 50ps to several nano seconds and the power consumption is ultra small. We have measured a Gaussian impulse with pulse-width of 800ps, amplitude of 48mV, and average power of 200muW at 100MHz pulse repetition frequency. The impulse generator is a key component in both UWB transmitter and receiver. This developed Gaussian impulse generator building block can be further used to generate higher derivative order Gaussian monocycle pulses or another kind of pulse waveform needed for UWB systems