Pulse generators capable of generating pulses with widths under approximately 100 picoseconds are often termed as “microwave pulsers” and typically generate these ultra-short pulses using Step recovery diode (SRD) or Nonlinear Transmission Line (NLTL) methods. Step Recovery Diode pulse generators are inexpensive but typically require several volts of input drive level and have a moderately high level of random jitter (usually undesirable variation in the time at which successive pulses occur).
NLTL-based pulse generators generally have lower jitter, but are more complex to manufacture and do not suit integration in low-cost monolithic ICs. A new class of microwave pulse generation architecture, the RACE (Rapid Automatic Cascode Exchange) pulse generation circuit is implemented using low-cost monolithic IC technology and can produce pulses as short as 1 picosecond, and with repetition rates exceeding 30 billion pulses per second. These pulsers are typically used in military communications applications, and low-power microwave transceiver ICs. Such pulsers, if driven by a continuous frequency clock, will act as microwave comb generators, having output frequency components at integer multiples of the pulse repetition rate, and extending to well over 100 gigahertz.