High-Power Microwave Generation by Compact Linear Transformer Driver Technology
Abstract
The efficient generation of high-power microwaves (HPM) from compactgenerating equipment is of critical importance to the United States Navy and Department of Defense (DoD). Applications include: radar, signal jamming, electronic warfare, counter IED (improvised explosive device), and vehicle stoppers. Example systems where HPM is critical include the Patriot Missile and the Aegis Combat/Weapon System. This project will explore the use of compact linear transformer driver (LTD) technology to drive various gigawatt-class, narrow-band (~1 GHz), high-power microwave (HPM) sources. LTDs are low-voltage, low impedance drivers. An LTD-driven HPM source could become one of the most compact, lowvoltage, GW-class HPM sources available for ONR/DoD directed energy programs. To obtain this performance, a rich assortment of physics issues will be studied. For example, as we increase the driver power, electrode plasmas (particularly from contaminants adsorbed ontoelectrode surfaces) can become problematic. If plasmas form in the anode-cathode gap with densities >1e10 electrons/cc, then L-band microwaves (1 GHz) can become attenuated significantly. We will study these low-density power flow plasmas by combining particle-in-cell simulations with experimental measurements from a vast array of diagnostics, including energetic particle detectors, Zeeman and Stark spectroscopy, self-emission imaging, and laserbased probing and imaging techniques. The use of LTD technology to drive an HPM source is advantageous for several reasons: First, the driver impedance and driver voltage is tunable, because LTD systems are modular. The PI will be assembling a 4-cavity LTD facility called BLUE (Bestowed LTD from the Ursa-minor Experiment) at the University of Michigan (UM). The driver impedance of BLUE can be varied from 1 to 30 ohms. Second, the pulsed-power components in LTDs are completely encased in metal, thus minimizing stray high-voltage fields and electrical interference. Third, LTDs can be rep-rated up to (and possibly beyond) 0.1 Hz, thus increasing the average power. Additionally, rep-rating has the potential benefits of electrode conditioning and decontamination, therefore allowing us to emulate standard industry practices in the fabrication of commercial microwave tubes. The effects of various reprates will be tested directly.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 26, 2018
- Source ID
- N000141812499
Entities
People
- Ryan Mcbride
Organizations
- Board of Regents of the University of Michigan
- Office of Naval Research
- United States Navy