A PPM Gaussian pulse generator for ultra-wideband communications

A Gaussian pulse generator incorporating a pulse position modulator for use in an ultra-wideband or impulse radio system is described. The pulse generator is preceded by a programmable pulse-position modulator and consists of a cascade of complex first-order systems, which, in turn, are made up of differential pairs employing partial positive feedback. The resulting PPM Gaussian pulse generator has been designed to be implemented in AMS 0.35/spl mu/m CMOS IC technology. Simulations predict the correct operation of the circuit for supply voltages of 3.3Vand a power consumption of 95mW. The output monocycle indeed approximates a Gaussian monocycle very well and has a pulse duration of about 230ps. Proper modulation of the pulse in time is confirmed.

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