High-Power Microwave Generation With Photoconductors

This paper describes an unconventional method for the generation of high-power microwave (HPM) with orders of magnitude higher in power and energy than competing concepts. The method brings together several synergistic concepts. First, microwaves are synthesized cycle by cycle (digital synthesis) by the discharge of charged transmission lines. The method presented here generates a bipolar pulse with substantial impedance transformation. Second, photoniconswitching via photoconductors is used to provide coherent timing. Third, the generation of HPM at extremely low impedance takes advantage of a fortuitous match between the peak Poynting power associated with thin films and high current density related to very high carrier concentration in photoconductors. Finally, unique HPM circuitry, termed a Switch Bypass Source circuit, is presented that affords multiple cycle generation and high pulse energy which avoids cascading switch losses. The combination of these techniques transforms HPM technology from the present level of gigawatts and hundreds of joules per pulse to levels that are orders of magnitude higher.