Balanced pulse generator for UWB radar application

A balanced pulse generator delivering high repetitive pulses of high voltage amplitude and pulse widths in the picosecond region is described. The output pulses of a npn silicon power transistor operating in an avalanche mode, drive a step recovery diode (SRD) waveform edge sharpener. As commercially available ultra-fast SRDs have commonly low breakdown voltage, the powerful avalanche pulses with a high voltage of 65V are first split into balanced pulses using a balun transformer. Then the balanced pulses with half amplitude are fed to ultra-fast SRD pulse shaping circuits exhibiting nearly balanced pulses with peak values of 25V (26V) and pulse widths of 140 ps (135 ps). The pulses are intended for application in near-field UWB radar sensors.