Sub-Nanosecond Pulse Generation using Resonant Tunneling Diodes for Impulse Radio

The application of resonant tunneling diodes (RTD) for generation of Gaussian-like monocycles and modified Hermite pulses of 2^nd order for ultrawideband (UWB) impulse radio is investigated in this paper. A circuit concept employing a pin-photodiode and two RTD based monostable bistable threshold logic elements (MOBILE) is introduced. The circuit generates, depending on a digital optical input signal, arbitrary pulse cycles at the output of the circuit. Based on the measurement result of a single MOBILE, simulations are presented that show the capability of the proposed circuit to generate pulses like single Gaussian pulses, Gaussian monocycles, and 2^nd-order modified Hermite pulses. Experimental verification of positive and negative gaussian pulses with a width of 100 ps is demonstrated for a pulse repetition rate of 13.2 Gpulses/s.