Ultra-wideband n-bit digitally tunable pulse generator

This paper presents a low-cost ultra-wideband (UWB) pulse generator that can vary the pulse duration digitally by using a step recovery diode (SRD), microstrip transmission lines and PIN diodes. First, a sharp edge is generated by using a SRD. Through the use of transmission lines and the PIN diodes, a pulse is formed from the sharp edge. Based on the number of transmission lines (N), the duration of the pulse can be varied in 2/sup N/ steps. The UWB pulse generator circuit is implemented on FR-4 substrate using microstrip line technology and UWB pulses with durations of 550 to 1750 psec are measured.