Microwave susceptibility experiments

In certain experimental environments, systems can be affected or damaged by microwave pulses. Tests were conducted to understand the phenomenology of microwave susceptibility of system components and subsystem components. To date, experiments concentrated on bipolar transistors, similar to what might be used in discrete analog circuits, and on CMOS RAM chips, which might be used in a computer memory system. A decrease in failure energies for both the transistor and the integrated curcuit as I shortened the microwave pulse width was observed. An S band (2.86 GHz) transmit/receive (T/R) tube was tested both at S band and at X band (8.16 GHz). The S band pulse had limitations in rise-time from zero power, which had an effect on the amount of power that could be transmitted through the T/R tube; as much as 0.7% of the incident power passed through the tube. All tests were conducted in closed-waveguide or coax test-fixtures, in contrast to the anechoic chambers utilized by other experimenters. Both S band and X band Klystron generators were used. For very high power (greater than 1 MW), an additional pulse-compression cavity at S band was used.