Truly balanced step recovery diode pulse generator with single power supply

Abstract

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 a truly balanced output. The diode biasing is integrated with the switching circuitry to improve the compactness of the design. Two versions of the circuit with lumped and distributed pulse forming networks have been tested. The pulse parameters for distributed pulse shaping network were: rise/fall time (10-90%) 183 ps, pulse width (50-50%) 340 ps, pulse peak to peak voltage 896 mV (12.05 dBm peak power) and for the lumped case: rise time (10-90%) 272 ps, fall time (90-10%) 566 ps pulse width (50-50%) 511 ps, pulse amplitude /spl plusmn/1.6V (17 dBm peak power). In both cases excellent balance of the two pulses at the output ports can be observed. It should be noted that above parameters were obtained with typical inexpensive RF components. The circuit reduces the complexity of the design because of the lack of broadband baluns required for UWB balanced antennas. The circuit may be used as part of a UWB transmitter.