John Barrett, Pawel Rulikowski

Truly Balanced Step Recovery Diode Pulse Generator with Single Power Supply

A space efficient and simple circuit for ultra wideband (UWB) balanced pulse generation is presented. The pulse generator uses a single step recovery diode to provide truly balanced output. The diode biasing is integrated with the switching circuitry to improve the compactness of design. Two versions of the circuit with lumped and distributed pulse forming networks have been tested. The pulses’ parameters for distributed pulse shaping network were: rise/fall time (10- 90%) 168ps, pulse width (50-50%) 335ps, pulse amplitude ±880mV (11.9 dBm peak power) and for the lumped one: rise time (10-90%) 272ps, fall time (90-10%) 566ps pulse width (50-50%) 511ps, pulse amplitude ±1.6V (17 dBm peak power). In both cases excellent balance of two pulses at the output ports can be observed. It is worth to mention that above parameters were obtained with typical inexpensive RF components. The circuit reduces the complexity of the design because of lack of broadband baluns required for UWB balanced antennas. The circuit may be used as a part of an UWB transmitter. 1.