An X-Band System for Diagnostics During Pulsed Microwave Breakdown of a Shock Generated Plasma

摘要

The report describes the circuits, equipment, and experimental approach used for analysis of 'breakdown' resulting from a high-power, X-band microwave pulse incident on a shock-produced plasma. The shock-ionized gas passes through a test section where it is simultaneously heated by a pulse at 9.58 GHz and probed by a low-power CW signal at 9.385 GHz. Breakdown is observed by recording the incident, transmitted and reflected amplitudes of the heating pulse, and through bridge analysis of the diagnostic signal. A description is also given of electric-field probes used to determine the instantaneous field configuration in the test section during breakdown. As this report is concerned specifically with the equipment and measurement techniques employed in investigating the breakdown problem, detailed test results will be presented in a subsequent report. (Author)